The Escalating Conflict with Hezbollah in Syria
Hezbollah and Iran have accumulated a substantial amount of weapons and fighters in Syria that pose a threat to the United States and its allies in the region. In response, Israel has conducted a growing number of strikes against Iranian, Hezbollah and other targets in Syria. An escalating war has the potential to cause significant economic damage, lead to high numbers of civilian casualties and internally displaced persons, and involve more countries in the region than did the 2006 Lebanon War. The stakes are high, making it critical for Washington to help prevent such an escalation.
Over the past several years, Hezbollah has amassed significant capabilities in Syria with the help of its close ally, Iran, and today poses a growing asymmetric threat to the United States, Israel, Jordan, and other countries in the region. Hezbollah forces in Syria have improved their operational and tactical combat skills, trained and equipped thousands of militants as part of its growing network of Shi’a militias, and stockpiled an impressive arsenal of standoff weapons like Fateh-110/M-600 guided missiles, Karrar unmanned armed drones, Shahab-1 and Shahab-2 short-range ballistic missiles, Toophan anti-tank missiles, and possibly chemical weapons. In addition, much of Hezbollah’s arms are shipped through, or potentially manufactured in, Syria—making the country a critical transit hub. Hezbollah is perhaps the best-trained, best-equipped, and most capable terrorist organization in the world, and these developments have raised the prospects of a wider conflict in the Middle East.
Israeli leaders are already on a war footing because of the actions of Hezbollah and its ally, Iran. For the past several years, Israel has regularly conducted attacks against Hezbollah, Iranian, and Syrian targets in Syria. What is new, however, is Israel’s decision to step up attacks to deter Iran and Hezbollah from future expansion in Syria—and perhaps to deter Syria from allowing Iran and Hezbollah to undertake this expansion. “I know one thing for certain,” said Israeli Defense Minister Avigdor Lieberman recently. “We will not allow the Iranians to base themselves in Syria and there will be a price for that. We have no other choice. To agree to an Iranian presence in Syria, it’s agreeing to the fact that the Iranians will put a noose around your neck.”1 Israel has conducted over 100 strikes against Hezbollah and Iranian targets in Syria since the beginning of the Syrian war.2 Of the 101 Israeli airstrikes analyzed by CSIS, over two-thirds were against missile-related targets.3 Hezbollah’s deepening involvement in Lebanese and regional politics, including the expansion of seats in Lebanon’s Parliament by Hezbollah and its political allies in the May 2018 elections, suggest that a future war involving Israel, Hezbollah, and even Iranian forces could be more violent and expansive than the 2006 Lebanon War.
These recent developments raise several questions. What are Hezbollah and Iranian long-term goals in Syria? What are Hezbollah’s capabilities, how have these capabilities been transformed, and what threat does Hezbollah pose? Finally, what are the implications for the United States and its allies? To answer these questions, this CSIS Brief compiles a range of data—including new information—about the location of Hezbollah, Iranian, and allied militias in Syria; Israeli airstrikes in Syria; and satellite imagery of military bases and other targets. The brief is organized into four sections. The first analyzes Hezbollah and Iran’s political and military objectives in Syria. The second section assesses Hezbollah’s capabilities and actions. The third examines the broader strategic threat from Hezbollah. And the fourth section outlines potential challenges and opportunities for the United States and its allies. In addition, an appendix provides examples of Hezbollah weapons and systems in Syria.
Hezbollah and Iranian Goals in Syria
Hezbollah’s objectives in Syria are closely tied to Tehran’s broader national security goals. Since Hezbollah’s creation, Iran has played a significant role in training, supplying, and funding the group. Iranian leaders seek to expand their security, economic, cultural, and religious interests regionally, and to ensure the survival of the regime domestically.4 The 1979 revolution—and the global reaction to the revolution—significantly impacted the views and politics of Supreme Leader Ayatollah Ali Khameini. Iranian leaders seek to expand Iran’s network of influence through regional allies and buffer zones, including through Hezbollah.5
Israel has conducted over 100 strikes against Hezbollah and Iranian targets in Syria since the beginning of the Syrian war.
Since the Syrian war began in 2011, Iran has provided an unprecedented level of political, financial, cyber, and military support to the Syrian government to prevent the overthrow of the Assad regime and to balance against Iran’s main adversaries, including the United States, Israel, and Saudi Arabia. Tehran has deployed as many as 2,500 soldiers on the ground—from Islamic Revolutionary Guard Corps (IRGC) operatives to regular Iranian forces—and utilizes locations like Tiyas air field (or T-4) in Homs, Al-Shayrat airfield in Homs, and Al-Kiswah base south of Damascus.6 Iran has also supported Hezbollah and other militias in Syria, including perhaps 8,000 to 12,000 Shi’a foreign fighters from countries like Afghanistan, Yemen, and Iraq.7 The external operations department of the IRGC-Quds Force, a special forces unit of the IRGC responsible for extraterritorial operations, has been critical in organizing these militias.
Hezbollah leader Hassan Nasrallah remarked, “I will tell you that if the whole world comes together to force us to leave Syria, they will not be able to evict us.”
Hezbollah retains a close relationship with Iran, though it operates as its own political-military organization. Hezbollah’s objectives in Syria can be divided into two broad categories: political and military.
Political goals: Hezbollah’s political objectives in Syria include ensuring the survival of the Assad regime; protecting—and expanding—Hezbollah’s political power and influence; balancing against Israel and the United States; stemming the spread of Sunni Salafi-jihadist and other “takfiri” groups; and defending Shi’a communities.8 As Hezbollah leader Hassan Nasrallah warned, “Should Syria fall into the hands of the Americans, the Israelis, the takfiri groups and America’s representatives in the region which call themselves regional states, the resistance will be besieged and Israel would reenter Lebanon, impose its conditions on Lebanon, and renew its greed and projects in it.”9 The overthrow of the Assad regime by Sunni rebels or countries like the United States, Saudi Arabia, and Israel would pose a severe threat to Hezbollah and could lead to Hezbollah’s encirclement in Lebanon. Consequently, Hezbollah leaders remain committed to operations in Syria as long as Bashar al-Assad wants them there. In June 2018, Hassan Nasrallah remarked, “I will tell you that if the whole world comes together to force us to leave Syria, they will not be able to evict us,” and continued on to state that Hezbollah would only leave Syria "when the Syrian authorities demand it."10 Hezbollah’s broad political goals have long been to protect Shi’a Islam and spread Shi'a activism, particularly in Lebanon, and to balance against—and eventually to destroy—Israel.11
The Syria conflict has improved Hezbollah’s urban warfare capabilities, provided real-world battlefield coordination with Iran and Russia, and augmented its collaboration with less-sophisticated Iranian battlefield proxies from Afghanistan and other countries.
Hezbollah has orchestrated a sophisticated information campaign in Syria to support its political and military objectives, using television, radio, print media, the Internet, and social media to bolster its narrative. Its media outlets collaborate with Iranian state media on broader messaging, while simultaneously addressing local grievances. Hezbollah has used an intensive propaganda and media campaign to portray itself as the self-proclaimed protector of Shi’a communities that straddle the Lebanese-Syrian border. From the outset of the Syrian war, Hezbollah has helped protect Shi’a populations near the western Syrian city of al-Qusayr and other areas in Syria near Hezbollah’s stronghold in Lebanon’s Beqaa Valley.12 Hezbollah has also vowed to protect Shi’a holy sites around Damascus, even producing video games that allow players to fight as Hezbollah militants. One of the most recent video games, titled “The Holy Defense: Protecting the Homeland and the Holy Sites,” was released in February 2018. It allows players to defend Shi’a holy sites, such as the Sayeda Zeinab in southern Damascus, against Islamic State attackers.13
Military goals: While increasingly unlikely, the fall of the Assad regime in Syria would represent a significant setback for Hezbollah, since it receives most of its arms through Syria. Other neighbors, such as Turkey, have cracked down on Hezbollah shipments through their territory. Consequently, an important military objective includes preserving—and potentially expanding—the use of Syrian territory as a logistical route for transporting Iranian missile parts and other material. Hezbollah also seeks to strengthen its own military capabilities in case of a possible war with Israel. Hezbollah leaders have used the conflict in Syria to expand their footprint in the country to increase their influence and surround Israel. The next section provides more details about Hezbollah’s military power and operations.
Hezbollah’s Capabilities and Actions in Syria
To achieve its political and military goals, Hezbollah has redirected significant personnel, capabilities, and resources from Lebanon to Syria.15 The Syria conflict has improved Hezbollah’s urban warfare capabilities, provided real-world battlefield coordination with Iran and Russia, and augmented its collaboration with less-sophisticated Iranian battlefield proxies from Afghanistan and other countries. In the early stages of the Syrian war, Hezbollah’s support for the Assad regime was limited to small numbers of trainers and advisers. Hezbollah leaders didn’t confirm their activities in Syria until 2013, when Hasan Nasrallah defiantly announced that he was sending fighters to aid the Syrian government, adding: “I have always promised you victory, and I promise victory again.”16 Today, Hezbollah has between 7,000 and 10,000 fighters in Syria, its largest deployment anywhere in the world outside of Lebanon.17
Hezbollah forces have amassed a range of weapons and systems in Syria, such as the Fateh-110/M-600 short-range ballistic missile, Shahab-1 and Shahab-2 short-range ballistic missiles, Toophan anti-tank guided missiles, Kornet man-portable anti-tank guided missiles, M113 armored personnel carriers, T-72 main battle tanks, Karrar unmanned combat aerial vehicles, and Katyusha rockets.18 The appendix provides more details about these weapons and systems. Hezbollah’s armed drone capabilities are among the most advanced of any terrorist group in the world, and it has destroyed Islamic State targets in Syria using Karrar armed drones.19 In addition, Hezbollah may have stockpiled chemical weapons in Syria, including chlorine.20 We found no evidence in Syria that Hezbollah has stockpiled or used explosively formed penetrators (EFPs), which are shaped charges designed to penetrate armor. But this could change. Iran, Hezbollah, and other proxies have used EFPs in other countries, including Iraq, Afghanistan, and Yemen.21 Still, Hezbollah’s capabilities—particularly its standoff missiles—present a threat to the region.
Today, Hezbollah has between 7,000 and 10,000 fighters in Syria.
Hezbollah has used these capabilities in support of operations in Syria and Lebanon. It has defended or retaken Druze, Shi'a, Alawite, Sunni, and Christian villages around the Syrian city al-Qusayr, as well as several Shi’a-majority suburbs of Damascus like Sayyida Zeinab.22 In August 2014, in a rare instance of cooperation, Islamic State and Jabhat al-Nusrah militants launched a joint offensive and briefly held the Lebanese town of Arsal. They eventually retreated to positions in the mountains along the Lebanese-Syrian border following military operations by the Lebanese Armed Forces (LAF). In May 2015, Hezbollah militants were involved in heavy fighting in the Qalamoun region of Syria, near the Lebanese border. In July 2017, Hezbollah launched an offensive against al-Nusrah positions around Baalbek, Lebanon, near the Syrian border, as highlighted in Figure 2.23 Hezbollah used the operation to rally domestic Lebanese support around its campaign in Syria, trying to bolster its image as the protector of Shi’a communities against Sunni militancy.24 As Hezbollah leader Hassan Nasrallah remarked in response to those who questioned Hezbollah’s involvement in Syria, “Ask the people of Hermel. Continue on to the villages around Hermel, to the Bekaa . . . and to Baalbek . . . then answer your own question.”25 Nasrallah was apparently referring to towns cleared of al-Nusrah control or influence.
Hezbollah has also trained, advised, and assisted Shi’a and other proxies in Syria. Collectively known as Al-Muqawama al-Islamiyah fi Suria, or “the Islamic Resistance in Syria,” the militias are similar to those trained by Hezbollah Commander Ali Musa Daqduq in Iraq, known as the Asaib Ahl al-Haq units. Examples of Hezbollah-trained militias in Syria include:
- Quwat al Ridha (or Ridha Forces), which have operated in such Syrian governorates as Homs;
- Al-Ghaliboun: Saraya al-Muqawama al-Islamiyah fi Suria (or The Victors: The Companies of the Islamic Resistance in Syria), which have been active in governorates like Daraa and Quneitra;
- Liwa al-Imam al-Baqir (or Baqir Brigade), which has deployed to such governorates as Aleppo.27
In addition, there are roughly 8,000 to 12,000 other Shi’a foreign fighters in Syria from countries like Afghanistan, Yemen, and Iraq.28 The IRGC-QF’s external operations department, Department 400, has been critical in organizing these militias.
Over two-thirds of the strikes analyzed by CSIS hit missile-related targets, such as storage warehouses, transportation convoys, and missile batteries.
The bulk of Hezbollah’s forces and proxy militias have been deployed along the Lebanese-Syrian border, where there are large pockets of Shi’a communities and shrines—and near Hezbollah’s stronghold in southern Lebanon. Hezbollah has also deployed fighters deeper into Syria, including around the cities of Damascus and Homs. There have been reports of Hezbollah fighters as far away as Deir al-Zour governorate in the Middle Euphrates River Valley.29 More recently, Hezbollah forces have deployed to Syrian military positions near the Israeli-Syrian border. Figure 3 shows the presence of Hezbollah, Iranian, and other militias in Syria, according to CSIS estimates. An interactive version of this map is available on the CSIS website.
Figure 3: Hezbollah, Iranian, and Other Allied Militias in Syria, June 201830
The Strategic Threat
There are several concerns about Hezbollah’s trajectory. First, Hezbollah continues to develop its military proficiency and increase its standoff capabilities, making it a more dangerous adversary in the event of a future Hezbollah or broader Iranian conflict with Israel, the United States, or other countries. Hezbollah has stockpiled and deployed larger quantities and types of weapons—particularly rockets and missiles—that can reach targets in countries like Israel, Jordan, and Turkey. Hezbollah and Iran have deployed their forces close to strategic locations like the Golan Heights along the Israel-Syrian-Lebanese border, threatening Israel. Second, Hezbollah and Iran’s decision to train and equip Shi’a and other militias in Syria gives them a larger network of proxies to extend their power and influence in the Middle East, South Asia, and other regions. Hezbollah and Iran also have access to a larger multinational pool of personnel for other conflicts or terrorist operations. These developments threaten U.S. interests in Iraq, Afghanistan, Yemen, and other countries. Third, Hezbollah and Iran have expanded and transformed their influence in Syria by deploying their forces, building proxies, and establishing a relationship with the Assad regime and non-state actors.
In response to these developments, Israel has carried out over 100 strikes in Syria since the beginning of the war—with a rise in activity in recent months. These strikes have ranged from artillery barrages along the Israeli-Syrian border to airstrikes that have reached deeper into Syria. Over two-thirds of the strikes analyzed by CSIS hit missile-related targets, such as storage warehouses, transportation convoys, and missile batteries. On May 24, 2018, for example, Israeli Air Force fighters struck munitions depots and other targets at al-Qusayr (or Daba’a) airbase in the western sector of Homs governorate, allegedly killing a senior Hezbollah commander.31 On May 9 and 10, shortly after the United States pulled out of the Iran nuclear deal, Israeli F-35 stealth fighters, F-15Is, F-16Is, and other aircraft attacked over 20 Iranian targets in Syria—including Iranian logistical bases and outposts—with over 70 cruise missiles and precision-guided bombs.32 On April 29, Israeli aircraft hit 13 buildings at the 47th Brigade military base near the city of Hama, targeting as many as 200 surface-to-air missiles. On April 9, Israeli aircraft attacked Syria’s T-4 air field in Homs governorate, killing seven Iranian military personnel.33 As a senior Israeli Air Force officer remarked, “We are continuing with our operational mission against the arming of Hezbollah and Iranian moves to establish themselves in Syria. As far as we are concerned, anywhere we identify consolidation [of Iranian or Hezbollah forces] or the introduction of weapons, we act.”34
Figure 4 plots Israeli strikes against Hezbollah, Iranian, and Syrian targets collected by the CSIS Transnational Threats Project through original open-source research. Most of Israel’s attacks were in southwestern Syria, near the Israeli border. But a few operations were against major bases used by Hezbollah, Iran, and other proxy militias in other areas, such as T-4 air field in Homs, the airbase north of al-Qusayr, and Damascus International Airport. In June 2018, Israeli aircraft apparently struck Shi'a militia targets near the southeastern town of al-Bukamal, near the Syria-Iraq border.
The rise in the number of strikes in 2017 and 2018 shows that Israel has been increasingly concerned about the encroachment of Hezbollah and Iran. The Israeli military has conducted strikes to retaliate against Iranian actions, such as rocket launches; push Hezbollah and Iranian positions further from its border; and degrade Hezbollah and Iranian capabilities, especially missile capabilities. An interactive version of this map is available on the CSIS website.
Figure 4: Israeli Airstrikes in Syria, 2013–201835
Of the 101 Israeli strikes analyzed by the CSIS Transnational Threats Project through open-source research, more than two-thirds were against missile-related targets. CSIS found that at least 42 of the 101 strikes were on missile-related facilities, while 15 of the 101 strikes were on convoys allegedly carrying missile parts or technology. In addition, 34 of the 101 Israeli strikes were retaliatory. CSIS counted a total of 47 Israeli strikes against Hezbollah targets, 40 strikes against Syrian targets, and 14 strikes against Iranian targets. CSIS counted 12 strikes in 2013; 8 strikes in 2014; 21 strikes in 2015; 10 strikes in 2016; and 22 strikes in 2017. As of June 1, 2018, we recorded an unprecedented number of strikes—28—only five months into the year.36
Battles in areas like Damascus, Homs, and Aleppo have resulted in high numbers of Hezbollah casualties.
We also used satellite imagery to analyze specific targets. The Israelis struck a Syrian military facility at Al-Kiswah in southern Damascus four times in 2017 and 2018. Figure 5 is a satellite image showing the overview of the military site at Al-Kiswah, where Israel conducted airstrikes in December 2017 and May 2018 on alleged Iranian targets. Figures 6 through 9 depict the satellite imagery of the specific targets before and after Israeli strikes. Figures 6 and 7 show the destruction of some missile-related storage facilities at Al-Kiswah military base, following a December 2017 Israeli attack. The photos on the left show the location before the Israeli strikes, and the photos on the right show the same location after the strikes. Figures 8 and 9 include satellite imagery of another missile-related location at Al-Kiswah after a May 2018 Israeli attack. Again, the photos on the left feature the location before the Israeli strikes, and the photos on the right feature the same location after the strikes.
The satellite imagery suggests several issues. First, Israeli strikes were precise. Israeli aircraft destroyed all or parts of specific buildings or trucks—but left undamaged infrastructure or trucks only a few feet away. Second, the imagery suggests that Iran and Hezbollah have utilized both fixed and mobile sites to store or transport missiles and missile parts. Figures 6, 7, and 9 are infrastructure targets, such as buildings. But Figure 8 indicates that the targets were trucks, presumably because they were transporting material such as missile parts.
Figure 5: Overview of Alleged Missile-Related Storage Facilities at Al-Kiswah
Figure 6: Before and After Satellite Imagery of the December 2017 Israeli Airstrikes on Alleged Missile-Related Storage Facilities at Al-Kiswah
Figure 7: Before and After Satellite Imagery of the December 2017 Israeli Airstrikes on Alleged Missile-Related Storage Facilities at Al-Kiswah
Figure 8: Before and After Satellite Imagery of May 2018, Israeli Airstrikes on Alleged Missile-Related Transportation Targets at Al-Kiswah
Figure 9: Before and After Satellite Imagery of May 2018, Israeli Airstrikes on Alleged Missile-Related Storage Facilities at Al-Kiswah
Moving forward, U.S. and Israeli officials should remain concerned that Iran, Hezbollah, and their proxies will continue—and even increase—their presence and stockpile standoff weapons in Syria. In June 2017, Hassan Nasrallah exacerbated these and other fears when he promised that “thousands, even hundreds of thousands of fighters from Iraq, Yemen, Iran, Afghanistan and Pakistan” would fight against Israel. Following this statement, Yemen’s Abdul-Malek al-Houthi, a leader of the Houthi movement, pledged his fighters. So did Sheikh Akram al-Kaabi, whose Iraqi Shi’a Harakat Hezbollah al-Nujaba militia formed a “Golan Liberation Brigade.”37
U.S. and Allied Considerations
In crafting policy options, the United States and its allies should consider several issues: exploit dissent, encourage Russia to pressure Iran and Hezbollah, preserve a limited U.S. military presence in or around Syria to balance against Iran and Hezbollah, and leverage U.S. diplomacy to prevent military escalation.
First, there are opportunities to exploit Hezbollah and Iranian vulnerabilities in Syria. Battles in areas like Damascus, Homs, and Aleppo have resulted in high numbers of Hezbollah casualties. Estimates range from several hundred to several thousand Hezbollah fighters killed, with the most likely estimates between 1,000 and 2,000 dead.38 Thousands of Hezbollah fighters have also been wounded. Among Hezbollah’s high-profile deaths were a senior Hezbollah commander in May 2018; Mustafa Badreddine in May 2016, a senior Hezbollah commander in charge of Syrian military operations; Abdel Hamid Mahmoud Shri in June 2017, a field commander nicknamed “Abu Mahdi”; and Ali Al-Hadi Al-Ashiq in October 2017, another senior Hezbollah military commander. Hezbollah’s presence in Syria has been controversial among some of its own members and supporters because of the high costs in blood and money, as well as concerns that the war in Syria has taken away its focus from priorities in Lebanon.39 “We are a resistance [movement], and you don’t do resistance by going to war in Syria,” said one former Hezbollah fighter. “I will gladly go to fight Israel. But I won’t send my sons to die in Syria.”40 Moving forward, the continuing death of Hezbollah fighters in Syria would likely increase pressure on the group to pull back its forces.
There are reports that the Syrian regime helped disguise Iranian-allied militia as its own fighters to avoid further Israeli airstrikes.
Second, the United States should encourage Russia to play a more assertive role in decreasing the Hezbollah—and even Iranian—footprint in Syria. Russian leaders have expressed concern about several issues, such as the proliferation of Shi’a militias in Syria; the presence of Iranian and Hezbollah forces, including near the Golan Heights; and the possible escalation of an Israeli-Iranian war. While this is unlikely to result in the complete removal of all Hezbollah and other Iranian-friendly forces from Syria, Russia could be helpful in mediating an escalating crisis between Israel and Iran, as well as restraining both sides. Moscow could also be useful in pushing for a reduction in the number and location of Hezbollah and Iranian forces and material in Syria, particularly as the Assad regime takes back territory during counterinsurgency operations. As Russian President Vladimir Putin acknowledged in May 2018, “We presume that, in connection with the significant victories and success of the Syrian army in the fight against terrorism, with the onset of a more active part, with the onset of the political process in its more active phase, foreign armed forces will be withdrawn from the territory of the Syrian Arab Republic.”41 Russian foreign minister Sergei Lavrov also remarked in May 2018 that all non-Syrian forces—which includes Hezbollah—should withdraw from Syria’s southern border with Israel “as soon as possible.”42 The United States and Russia should continue to push for the removal of Iranian and Hezbollah forces from southwestern Syria and allow the Syrian army to deploy to the border along the Golan Heights.
Third, the United States should continue to keep a military and intelligence presence in Syria—as well as in neighboring countries such as Jordan, Iraq, and Lebanon—to balance against Iran and Hezbollah. The United States, Jordan, and Russia established a temporary de-escalation zone in southwestern Syria in 2017 as a buffer to stem the flow of terrorists and additional refugees into Jordan, aid refugees in countries like Lebanon and internally displaced persons in Syria, and prevent Hezbollah and other Shi’a militias from moving closer to the Syrian-Israeli border.43 U.S. diplomacy will be critical to help negotiate future arrangements in southern Syria that protect Israel’s security. The United States will need to continue collecting and analyzing intelligence on Hezbollah and Iranian positions and activities in Syria. For instance, Hezbollah and Iran could agree to move units and material out of southwest Syria, but instead shift to new clandestine locations or attempt to better conceal their positions. There are reports, for instance, that the Syrian regime helped disguise Iranian-allied militia as its own fighters to avoid further Israeli airstrikes.44 The United States should also keep a military presence at bases like Al-Tanf in Syria’s Homs governorate. Withdrawing U.S. forces from Al-Tanf would likely open a southern corridor for Iran to move people and material from Iraq through Syria and into Lebanon. It would also allow Iran an additional route to transport advanced weapons technology, supplementing other ground and air shipments.
A war with Israel would likely be more destructive and span a wider geographic area than in 2006, which led to nearly 1,400 dead, over 6,000 wounded, nearly 1.5 million displaced persons, and billions of dollars in war damage and lost economic output and income.
Fourth, U.S. diplomacy will be critical to preventing an escalation in the conflict between Israel and Iran—including with Hezbollah. The political and military landscape in the region is much different today than during the Israeli-Hezbollah war in June and July 2006. Hezbollah has more advanced standoff weapons, improved cyber capabilities, more recruits, and more expansive forces in Syria—not just Lebanon—capable of striking Israeli targets. The 2006 conflict demonstrated the difficulty of rooting out Hezbollah sites in Lebanon’s heavily urbanized environment. Time has only expanded the nature of this problem set for Israel’s military. With Hezbollah’s success in Lebanon’s May 2018 parliamentary elections, Hezbollah is also a more significant political player in Lebanon. Israel could expand its military target set in a future war to include Lebanese government sites—threatening a wider conflict.
A war with Israel would likely be more destructive and span a wider geographic area than in 2006, which led to nearly 1,400 dead, over 6,000 wounded, nearly 1.5 million displaced persons, and billions of dollars in war damage and lost economic output and income.45 An escalating war has the potential to engulf at least Israel, Syria, Lebanon, and Iran in a region where there are already multiple wars. It could cause significant economic damage to countries like Lebanon and Israel, lead to high numbers of civilian casualties and internally displaced persons, and involve Russia more deeply than in the past. The stakes are high today, making it even more important for Washington to deter such escalation.
Appendix: Example of Hezbollah Weapons and Systems in Syria
System : Fateh-110
Description : The Fateh-110 is a short-range, road-mobile, surface-to-surface ballistic missile. Hezbollah apparently has the M-600 variant of the Fateh-110, which has a range of approximately 180 miles and can deliver a payload of up to 1,100 pounds.
System : Shahab-1 and Shahab-2
Description : The Shahab-1 and Shahab-2 are single-stage, liquid-propelled, short-range ballistic missiles. The Shahab-1 has a maximum range of nearly 200 miles, while the Shahab-2 has a maximum range of over 300 miles. The Shahab-1 and Shahab-2 missiles are the Iranian variants of the Russian SS-1C ‘Scud B’ and SS-1D ‘Scud C,’ respectively.
System : Toophan Anti-Tank Guided Missile
Description : The Toophan is an Iranian man-portable, semiautomatic command to line of sight (SACLOS) anti-tank guided missile. It is reverse-engineered from the American BGM-71 tube-launched, optically tracked, wire guided (TOW) missile. The Toophan can be deployed by small teams against tanks, armored vehicles, buildings, and other targets. It has a maximum firing range of over 2 miles, a warhead of roughly 8 pounds, and can pierce armor 22 inches thick.
System : 9M133 Kornet
Description : The 9M133 Kornet is a modern Russian man-portable, anti-tank guided missile intended for use against main battle tanks. The Kornet has a range of over 3 miles, a warhead of 15 pounds, and can pierce armor nearly 40 inches thick.
System : M113 Armored Personnel Carrier
Description : The M113 is a lightly armored personnel carrier first fielded by the U.S. army in 1962. It is versatile and capable of acting as a front-line vehicle and can also be used in support roles. The M113 is most commonly armed with a machine gun.
System : T-72 Main Battle Tank
Description : The T-72 tank is a Soviet second-generation main battle tank that entered production in 1971. The T-72 is lightweight, has a comprehensive nuclear, biological, and chemical (NBC) system, can reach speeds up to 50 miles per hour, and is usually equipped with the 125-millimeter 2A46 series main gun.
System : Karrar Unmanned Combat Aerial Vehicle
Description : The Karrar is an unmanned combat aerial vehicle and the first long-endurance, combat-capable Iranian drone. It has an operational range of over 600 miles, with a maximum speed of 560 miles per hour. The Karrar can be outfitted with conventional bombs or guided missiles, including precision ordinance.
System : Katyusha Multiple Rocket Launcher
Description : The Katyusha was originally a truck-mounted multiple rocket launcher first fielded by the Soviet Union in 1939. Today, there are numerous variants of the Katyusha, with maximum ranges between 2 and 7 miles. While the Soviet variant used 82 mm and 132 mm rockets, the Hezbollah variants are typically 107 mm and 122 mm. Note that reporters often incorrectly refer to most of Hezbollah’s unguided artillery rockets as “katyusha.” The shorter-range rockets can carry up to 64-pound warheads, while the longer-range rockets can carry up to 11-pound warheads. In comparison with the Soviet truck-mounted Katyusha, Hezbollah does not have many Multiple Rocket Launchers (MRLs), so the Katyusha is often fired one at a time.
Seth G. Jones holds the Harold Brown Chair, is director of the Transnational Threats Project, and is a senior adviser to the International Security Program at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Maxwell B. Markusen is an associate fellow and associate director of the CSIS Transnational Threats Project.
CSIS Briefs are produced by the Center for Strategic and International Studies (CSIS), a private, tax-exempt institution focusing on international public policy issues. Its research is nonpartisan and nonproprietary. CSIS does not take specific policy positions. Accordingly, all views, positions, and conclusions expressed in this publication should be understood to be solely those of the author(s).
© 2018 by the Center for Strategic and International Studies. All rights reserved.
 David Wainer and Henry Meyer, “Russian Missiles Alarm Israel, Stoking Risk of Next Syria Crisis,” Bloomberg, April 19, 2018, https://www.bloomberg.com/news/articles/2018-04-19/new-russian-weapons-alarm-israel-may-trigger-next-syrian-crisis; CSIS Transnational Threats Project estimates.
 CSIS Transnational Threats Project estimates. We only counted cases where we found open-source evidence of missiles or missile parts at the target location. However, we suspect the number of Israeli airstrikes against missile-related targets may be higher than two-thirds.
 Mehdi Haghighatkha, “Omgh-e Raahbordi-ye Iran: Baghdad ta Karakas [Iran’s Strategic Depth: From Baghdad to Caracas],” Borhan News, August 5, 2013, http://borhan.ir/NSite/FullStory/News/?Id=5630.
 See, for example, Misagh Parsa, Democracy in Iran: Why It Failed and How It Might Succeed (Cambridge, MA: Harvard University Press, 2016); Abbas Amanat, Iran: A Modern History (New Haven, CT: Yale University Press, 2017).
 Ben Hubbard, Isabel Kershner, and Anne Barnard, “Iran, Deeply in Syria, Expands ‘Axis of Resistance,’” New York Times, February 19, 2018, https://www.nytimes.com/2018/02/19/world/middleeast/iran-syria-israel.html.
 CSIS Transnational Threats Project estimates; Phillip Smyth, “Iran Is Outpacing Assad for Control of Syria’s Shia Militias,” Washington Institute for Near East Policy, April 12, 2018, http://www.washingtoninstitute.org/policy-analysis/view/iran-is-outpacing-assad-for-control-of-syrias-shia-militias. Our estimates of Shi'a foreign fighters are slightly lower than Smyth's estimates.
 The term “takfiri” refers to a Muslim who accuses another Muslim of apostasy, or nonbelief. We define Salafi-jihadist based on two criteria. First, the individual or group emphasizes the importance of returning to a “pure Islam,” that of the Salaf, the pious ancestors. Second, the group believes that violent jihad is a fard ‘ayn (a personal religious duty).
 Speech by Hassan Nasrallah, May 25, 2013, https://www.youtube.com/watch?v=3gw60_F28zY.
 Speech by Hassan Nasrallah, June 8, 2018. https://www.youtube.com/watch?v=9lSkqfQdHJ8.
 On Hezbollah more broadly see, for example, Joseph Daher, Hezbollah: The Political Economy of Lebanon’s Party of God (New York: Pluto Press, 2016); Matthew Levitt, Hezbollah: The Global Footprint of Lebanon's Party of God, rev. ed. (Washington, DC: Georgetown University Press, 2015).
 David Hirst, “Hezbollah Uses Its Military Power in a Contradictory Manner,” Daily Star (Beirut), October 23, 2012, http://www.dailystar.com.lb/Opinion/Commentary/2012/Oct-23/192380-hezbollah-uses-its-military-power-in-a-contradictory-manner.ashx.
 Sunniva Rose, “‘Holy Defence’: Hezbollah Issues Call of Duty to Video Gamers,” Middle East Eye, February 28, 2018, http://www.middleeasteye.net/news/holy-defense-hezbollah-launches-new-video-game-675819933.
 For an example of the game, see http://holydefence.com.
 Yaakov Lappin, “Israeli Military Chief Outlines Hizbullah’s Syria Commitment,” HIS Jane’s Defence Weekly, January 4, 2018, http://www.janes.com/article/76795/israeli-military-chief-outlines-hizbullah-s-syria-commitment.
 Speech by Hassan Nasrallah, May 25, 2013.
 CSIS Transnational Threats Project estimates.
 CSIS Transnational Threats Project estimates; David Daoud, “Hezbollah Is Preparing Syria as Second Battlefield against Israel,” Long War Journal, March 16, 2017, https://www.longwarjournal.org/archives/2017/03/hezbollah-is-preparing-syria-as-second-battlefield-against-israel.php ; Reuters Staff, “Hezbollah Uses Drones against Islamic State in Syria: Hezbollah-run Media,” Reuters, August 21, 2017, https://ca.reuters.com/article/topNews/idCAKCN1B11H4-OCATP ; Thomas Gibbons-Neff, “Hezbollah Has U.S. Armored Personnel Carriers,” Washington Post, November 16, 2016, https://www.washingtonpost.com/news/checkpoint/wp/2016/11/16/hezbollah-has-u-s-armored-personnel-carriers-but-how-did-they-get-them/?noredirect=on&utm_term=.32c1d4f2924b.
 See the alleged video footage of a Hezbollah drone strike in Reuters Staff, “Hezbollah Uses Drones against Islamic State in Syria.”
 See, for example, Gideon Kouts, “Former Syrian General: Hezbollah Is in Possession of Chemical Weapons,” Jerusalem Post, March 8, 2018, https://www.jpost.com/Middle-East/Former-Syrian-official-to-Maariv-Hezbollah-has-chemical-weapons-544567.
 On the use of EFPs by Iran, Hezbollah, or other proxies see, for example, Andrew deGrandpre and Andrew Tilghman, “Iran Linked to Deaths of 500 U.S. Troops in Iraq, Afghanistan,” Military Times, July 14, 2015, https://www.militarytimes.com/news/pentagon-congress/2015/07/14/iran-linked-to-deaths-of-500-u-s-troops-in-iraq-afghanistan/ ; Kimberly Kagan, Iran’s Proxy War against the United States and the Iraqi Government (Washington, DC: Institute for the Study of War, August 2007), http://www.understandingwar.org/report/irans-proxy-war-against-united-states-and-iraq ; Kareem Fahim and Liz Sly, “Lethal Roadside Bomb That Killed Scores of U.S. Troops Reappears in Iraq,” Washington Post, October 12, 2017, https://www.washingtonpost.com/world/middle_east/lethal-roadside-bomb-that-killed-scores-of-us-troops-reappears-in-iraq/2017/10/11/87c5a57c-aeb7-11e7-9b93-b97043e57a22_story.html?utm_term=.a804a8804d69 . Also see, Adam Entous, “US Sees Hand of Elite Iranian Unit in Afghanistan,” Reuters, September 21, 2009, https://www.reuters.com/article/idUSN21522027 ; and Michael Knights, “Defeating Iran’s Roadside Bombs in Yemen,” Washington Institute for Near East Policy, March 26, 2018, http://www.washingtoninstitute.org/policy-analysis/view/defeating-irans-roadside-bombs-in-yemen.
 See, for example, James Harkin, “A Hundred Tiny Hezbollahs,” Foreign Policy, May 15, 2016, http://foreignpolicy.com/2016/05/15/a-hundred-tiny-hezbollahs-syria-iran-shiite-guerrilla-warfare/ ; Agence France-Presse, “Shia Shrine Near Damascus Hit by Double Bomb Attack,” Guardian, June 11, 2016, https://www.theguardian.com/world/2016/jun/11/shia-shrine-near-damascus-hit-by-double-bomb-attack ; IHS Markit, “Jane’s World Insurgency & Terrorism,” https://ihsmarkit.com/products/janes-world-terrorism-insurgency.html.
 Tom Perry and Angus McDowall, “Lebanese Army, Hezbollah Announce Offensive against Islamic State on Syrian Border,” Reuters, August 18, 2017, https://www.reuters.com/article/us-mideast-crisis-lebanon-syria/lebanese-army-hezbollah-announce-offensives-against-islamic-state-on-syrian-border-idUSKCN1AZ03G.
 See, for example, Lina Khatib, “The Political and Security Fallout of the Battle of Arsal,” Carnegie Middle East Center, August 16, 2014, http://carnegie-mec.org/2014/08/16/political-and-security-fallout-of-battle-in-arsal-pub-56408.
 “Statement of Hassan Nasrallah on Television about the Course of the Joroud Arsal Battle,” Al-Manar TV, July 27, 2017.
 MrPenguin20, "Battle of Qalamoun," https://commons.wikimedia.org/wiki/File:Battle_of_Qalamoun.svg.
 See, for example, Phillip Smyth, “Lebanese Hezbollah’s Islamic Resistance in Syria,” Washington Institute for Near East Policy, April 26, 2018, http://www.washingtoninstitute.org/policy-analysis/view/lebanese-hezbollahs-islamic-resistance-in-syria.
 CSIS Transnational Threats Project estimates; and Smyth, “Iran Is Outpacing Assad for Control of Syria’s Shia Militias.”
 Lappin, “Israeli Military Chief Outlines Hizbullah’s Syria Commitment.”
 IHS Janes and open-source data collected by the CSIS Transnational Threats Project.
 TOI Staff, “Hezbollah Men, Including Commander, Said Killed in Syria Strike Blamed on Israel,” Times of Israel, May 29, 2018, https://www.timesofisrael.com/hezbollah-men-including-commander-said-killed-in-syria-strike-blamed-on-israel/ ; Charles Bybelezer, “Israel and Iran Revert Back to Familiar Patterns in Syria,” Jerusalem Post, May 28, 2018, https://www.jpost.com/Middle-East/Israel-and-Iran-revert-back-to-familiar-patterns-in-Syria-558530 ; Tamar Ben-Ozer and Yasser Okbi, “21, Including Iranians, Reported Killed in IAF Strike in Syria,” Jerusalem Post, May 27, 2018, https://www.jpost.com/Israel-News/21-including-Iranians-reported-killed-in-IAF-strike-in-Syria-558454.
 Yaniv Kubovich, “Israel Launched World’s First Air Strike Using F-35 Stealth Fighters, Air Force Chief Says,” Haaretz, May 24, 2018, https://www.haaretz.com/israel-news/security-aviation/with-iran-in-syria-israel-launched-world-s-first-air-strike-using-f-35-stealth-fighters-1.6110706 ; Amos Harel et al., “Israel Launches Most Extensive Strike in Syria in Decades after Iranian Rocket Barrage,” Haaretz, May 11, 2018, https://www.haaretz.com/israel-news/israel-launches-extensive-syria-strike-after-iranian-rocket-barrage-1.6073938.
 Judah Ari Gross, “Satellite Captures Destruction on Syrian Base after Alleged Israeli Strike,” Times of Israel, May 1, 2018, https://www.timesofisrael.com/satellite-captures-destruction-on-syrian-base-after-alleged-israeli-strike/.
 Kubovich, “Israel Launched World’s First Air Strike Using F-35 Stealth Fighters.”
 These data are from CSIS original open-source research. We identified more than 65 of the alleged 150 Israeli strikes and plotted them.
 Estimates are from the CSIS Transnational Threats Project. As noted in a previous footnote, we only counted cases where we found open-source evidence of missiles or missile parts at the target location. However, we suspect the number of Israeli airstrikes against missile-related targets may be higher than two-thirds.
 David Daoud, “How Hezbollah Will Use Foreign Fighters to Conquer Lebanon,” Haaretz, April 27, 2018, https://www.haaretz.com/opinion/.premium-hezbollah-s-plan-to-conquer-lebanon-1.6032874.
 CSIS Transnational Threats Project estimates; Colin P. Clarke, “A Glass Half Empty? Taking Stock of Hezbollah’s Losses in Syria,” Jerusalem Post, October 15, 2017, https://www.jpost.com/Opinion/A-glass-half-empty-Taking-stock-of-Hezbollahs-losses-in-Syria-507497 ; Ali Alfoneh, “Hezbollah’s Balancing Act Between Syria and Lebanon,” Atlantic Council, April 12, 2017, http://www.atlanticcouncil.org/blogs/syriasource/hezbollah-s-balancing-act-between-syria-and-lebanon.
 See, for example, Sune Engel Rasmussen and Nazih Osseiran, “Hezbollah Faces Rising Ill Will in Lebanon,” Wall Street Journal, May 3, 2018, https://www.wsj.com/articles/hezbollah-faces-rising-discontent-in-heartland-ahead-of-election-1525348801 ; Majid Rafizadeh, “Iran’s Fighters Are Dying in Syria—Will It Change Anything?” Huffington Post, December 6, 2015, https://www.huffingtonpost.com/majid-rafizadeh/irans-fighters-dying-in-s_b_8735658.html ; Jesse Rosenfeld, “Hezbollah Fighters Are Fed Up with Fighting Syria’s War,” Daily Beast, December 30, 2015, https://www.thedailybeast.com/bill-clinton-on-monica-lewinsky-how-about-all-the-women-i-promoted?ref=scroll.
 Rasmussen and Osseiran, “Hezbollah Faces Rising Ill Will in Lebanon.”
 Quoted in Tamara Qiblawi, “All ‘Foreign Forces’ to Leave Syria, Putin Tells Assad,” CNN, May 18, 2018, https://www.cnn.com/2018/05/18/middleeast/assad-putin-intl/index.html . Emphasis added.
 “Lavrov: Pullback of Non-Syrian Forces from Border with Israel Must Be Fast,” TASS, May 30, 2018, http://tass.com/politics/1007169.
 “Jordan Does Not Want Terrorists or Sectarian Militias at Border,” Jordan Times, April 21, 2018, http://www.jordantimes.com/news/local/jordan-does-not-want-terrorists-or-sectarian-militias-border%E2%80%99.
 See, for example, Raja Abdulrahim, “Iran-Backed Fighters Switch to Syrian Uniforms to Avoid Israeli Strikes, Rebels Say,” Wall Street Journal, June 8, 2018, https://www.wsj.com/articles/iran-backed-fighters-switch-to-syrian-uniforms-to-avoid-israeli-strikes-rebels-say-1528478351.
 Reuters Staff, “Factbox: Costs of War and Recovery in Lebanon and Israel,” Reuters, July 9, 2007, https://www.reuters.com/article/us-lebanon-war-cost/factbox-costs-of-war-and-recovery-in-lebanon-and-israel-idUSL0822571220070709.