Can the United States Equip Israel while Simultaneously Equipping Ukraine and Taiwan?

Audio Brief

A short, spoken-word summary from CSIS’s Mark Cancian on his Critical Questions “Can the United States Equip Israel while Simultaneously Equipping Ukraine and Taiwan?” 

Audio file

President Biden has stated U.S. intentions: “I made clear to Prime Minister Netanyahu that we stand ready to offer all appropriate means of support to the Government and people of Israel.” This aligns with half a century of U.S. policy. The problem is that this commitment occurs when the United States is also sending equipment to Ukraine to help it repel Russia's invasion and to Taiwan to strengthen it in the face of Chinese threats and provocations. Study after study reveals shortcomings in U.S. weapons and munitions stockpiles. Given these other commitments, can the United States keep Israel supplied, or is this beyond what even a superpower can do?

Q1: What military supplies will Israel need?

A1: The initial phase of the war―expelling the terrorists from Israeli territory after their October 7 invasion―is nearly over, but Israel will soon begin an attack into the Gaza Strip, whether by air and conventional ground forces or air and special forces. That will be intense, given the built-up nature of the terrain and the determination of the Hamas foot soldiers. Skirmishing has also occurred on Israel’s northern boundary with Lebanon, where a variety of militant groups, including Hezbollah, Iran’s close ally, occupy territory. Indeed, Iran supports Hamas and often calls for Israel’s elimination Israel might strike directly at its long-time adversary. A long and potentially large war looms with a heavy expenditure of munitions and, unfortunately, loss of life.

The densely populated nature of the Gaza Strip will put a premium on precision munitions, both ground and air delivered. There will also be a demand for stronger air defenses since Hamas has fired thousands of rockets at Israel. Indeed, the U.S. government is reported to have already sent precision-strike and air defense systems. Reports about airlift operations into Israel indicate urgency. Weapons usually go by sea since it is far cheaper.

Unlike in Ukraine, there will be less need for unguided artillery shells. Unguided artillery requires large volumes of fire to have the same effect as precision munitions and would endanger civilians. Further, the Israeli forces involved are smaller than those in Ukraine, and the likely length of the war will be shorter. Where Ukraine fires 6,000 to 8,000 rounds per day, week after week, month after month, Israel will fire fewer rounds over a shorter period. It will, therefore, have less need for resupply.

Similarly, although Israel appears to have lost several dozen armored vehicles in the most recent attacks, it still has hundreds. Emergency supply is probably unnecessary. The same holds for aircraft and mundane items like trucks. Israel may want some for postwar reconstruction, but losses are unlikely to be so high that it needs replacements to continue operations.

Q2: Are the needed weapons and munitions in short supply?

A2: Some important systems are, indeed, in short supply. However, before diving into shortfalls and trade-offs, it is important to note that most warfighting items are available in quantity. Of the 100 items listed in the Department of Defense’s latest fact sheet on military aid to Ukraine, only a dozen are known to be in short supply. Furthermore, some items with limited inventories, like High Mobility Artillery Rocket System (HIMARS) launchers, artillery cannon, and 155-millimeter unguided projectiles, are not relevant to Israel’s immediate needs.

The tables below show different kinds of precision munitions that Israel, Ukraine, and Taiwan use and illustrate areas where there may be shortages and trade-offs.

The following color coding applies to the tables:

  • Green: Widely available
  • Yellow: Available but with some limits
  • Red: Extremely limited—multiple allies want these weapons in addition to U.S. forces

The United States could meet partners’ needs for items coded yellow or red by accepting more risk in its own potential future wars, such as a conflict on the Korean Peninsula. Alternately, it could prioritize Israel in the near term, Ukraine in the midterm, and Taiwan in the long term. That spreads the risk. Yet, however the allocation is done, there is no getting away from trade-offs.

Remote Visualization

GMLRS: Guided Multiple Launch Rocket System (GMLRS) is a ground-launched medium-range precision-guided missile. Israel has its own version of GMLRS that it fires from U.S.-designed M270 launchers. Nevertheless, it could probably adapt to firing GMLRS if its inventories run low.

Excalibur: Excalibur is a GPS-guided artillery projectile. Israel uses a domestically produced precision artillery projectile, “TopGun.” Nevertheless, its howitzers are compatible with Excalibur and could adapt to using the Excalibur as the Ukrainians did.

ATACMS: Army Tactical Missile System (ATACMS) is a long-range missile fired from HIMARS and MLRS launchers. Israel is unlikely to need the range since targets in the Gaza Strip and Lebanon are nearby. GMLRS, which is fired from the same launchers, would be adequate and available in larger numbers. The range of ATACMS would only be needed for striking targets deep in Syria, which has an air defense system that the Israelis might want to avoid.

Javelin: Javelin is an infantry portable precision anti-tank weapon that became celebrated in the early phases of the Ukraine war. The Israelis have their own anti-tank weapons but could use Javelin if their own weapons ran short. Although Javelin is intended for use against tanks, which Hamas lacks, troops have frequently used it against other targets, such as crew-served weapons or field fortifications. Thus, the Israelis might find it useful in urban warfare. Because of Javelin’s low inventories, the United States could send a different anti-tank weapon, the Tube-launched, Optically Tracked, Wireless-Guided (TOW) missile system, which is available in large numbers. The United States has been shipping these to Ukraine as stockpiles of other anti-tank missiles have declined.

Remote Visualization

Hellfire: Hellfire is a helicopter and drone-fired missile. It is advantageous in close combat because of its ability to strike precisely with some standoff. The standoff keeps the slow and vulnerable helicopter away from adversary air defenses.

APKWS: Advanced Precision Kill Weapon System (APKWS) is a kit that gives precision guidance to unguided aviation rockets. They function tactically like Hellfire but are cheaper, though with less range and targeting flexibility. Ukraine has the missile but appears to be firing it from trucks rather than helicopters. Israel does not have APKWS now but might adopt it for an extended urban fight.

JDAM: Joint Direct Attack Munition (JDAM) is a kit that goes on a regular air-dropped bomb to give it precision guidance. Because it is low cost and available in large numbers, Israel would find it useful in a conflict in a built-up area. The short-range would not be a problem given Hamas’s lack of air defenses. The United States has surged production of JDAM in the past. Israel already has some JDAMs and will likely request more. Indeed, JDAM is reported to be in the initial shipments to Israel.

SDB/SDB II (StormBreaker): An air-delivered munition much like JDAM, Small Diameter Bomb (SDB) has some standoff capability and a smaller warhead, suitable for more precise effects. Israel is likely to use them extensively as a way to reduce collateral damage. SDB is also reported to be in the initial shipments to Israel.

“Bunker Buster” Munitions: Formally called munitions for deep and hardened targets, they are designed to attack targets that regular bombs, even the largest, cannot damage. Instead of bursting on the target’s surface, “bunker buster” munitions have mechanisms to penetrate deep into concrete or earth. The classic example is the GBU-28, though there are others. However, the inventory is not large because this is such a specialty weapon. The United States is reported to have built 160 GBU-28s and the Israelis bought 100. The Israelis would find them useful in attacking Hamas’s extensive underground system.

In addition, the United States has many air-launched long-range weapons, which allow aircraft to strike from outside an adversary’s air defense zone. However, this capability is not needed to attack targets in the Gaza Strip. Hamas's air defenses are weak, and the flying distance from Israel short. Standoff capabilities would be needed if Israel wanted to strike targets in Iran or Syria. Examples of such missiles include the Joint Air-to-Surface Standoff Missile (JASSM), and the Joint Standoff Weapon.

Remote Visualization

Patriot: The high-cost/high-capability Patriot missiles ($4.1 million each) are well suited for attacking adversary aircraft, cruise missiles, and ballistic missiles, such as the ones Iran possesses. However, the missiles are too scarce and expensive to use against Hamas's inexpensive artillery rockets.

Iron Dome: Iron Dome is the ideal system for defense against Hamas artillery rockets. The system was designed to counter the militant rocket threat, is not expensive, and is widely fielded. The missiles are coproduced by the United States and Israel. It is unsurprising, therefore, that Israel is reported to have requested more Iron Dome missiles. The United States can expedite production of missile components and fund Israeli production of additional systems. The United States also has two Iron Dome batteries it used for testing and could return to Israel.

Stinger/Avenger: Stinger is an infantry portable anti-air missile; Avenger is the truck-mounted version. The system is widely used around the world and effective against drones and aircraft. However, inventories are extremely limited, and production is slow. The United States has given Ukraine most of its available inventory, and Taiwan has likely received some as part of the presidential drawdown of equipment authorized by Congress.

The United States cannot help much with Israel’s two domestically produced air defense systems. David's Sling is for medium and long-range interceptions, much like Patriot. Arrow is designed to intercept ballistic missiles, which Hamas does not have but Iran does.

Bringing in new systems like National Advanced Surface-to-Air Missile System (NASAMS) would take too long because of the need for training and setting up a logistics pipeline.

Q3: Is there anything beyond precision munitions that Israel might need?

A3: Yes, there are several other capabilities that Israel will likely need almost immediately.

  • Intelligence support: Israel is certainly getting intelligence help from the United States, especially for hostage rescue. This likely takes the form of signals intelligence and overhead surveillance. For example, the United States may well be eavesdropping on terrorist conversations. Much of this will come from Middle East dedicated assets, but some might be diverted from Ukraine.
  • Spare parts: In peacetime, some part of a military’s equipment, anywhere from 10 percent to 50 percent, is inoperable because of a lack of spare parts or maintenance time. A surge of spare parts would expand the effective size of Israel’s force by making more equipment operational. There will be some competition for these spare parts since U.S., Ukrainian, and, often, Taiwanese forces need the same parts.
  • Uncrewed aerial systems: Israel already has many of these, but they are particularly helpful in built-up areas where finding the adversary is difficult but crucial. However, Ukraine also has a great need for such systems.
  • Counter-Drone Systems: Islamic militants have been clever in adapting commercial drones and may have received some from the Iranians. The militants will likely use these to strike back at Israel as Israeli forces attack the Gaza Strip. Therefore, a network of counter-drone systems will be needed. The United States has a wide variety of such systems, mostly developmental. However, Ukraine needs these in large numbers to counter Russian drones, which spot for Russia’s powerful artillery.

The longer the war goes on, the more resupply Israel will need as equipment is destroyed and munitions get used up. Items not needed in the first few weeks may be needed after a month. Therefore, this list will grow over time.

Q4: How will all this be paid for, and how much will it cost?

A4: Annually, Israel receives $3.8 billion of military aid, but this will not cover the costs imposed by this war. As a result, there will almost certainly be a supplemental appropriation, and, indeed, President Biden has stated his intention to ask for one. The core element of the supplemental will pay to replace equipment and munitions sent to Israel during the war. The supplemental may also include funds to rebuild Israel’s military after the war, and to help Israel repair the damage to buildings and infrastructure.

There may be economic support as well. The call-up of hundreds of thousands of reservists in a country of nine million disrupts the economy. Further, the tourist industry, which Israel is highly dependent on, has collapsed and may take months or years to rebuild. The United States has provided economic assistance to Israel in the past and could easily resume such assistance in an emergency like this.

The full need will not be known until the war is over. The United States might provide an interim amount. As a benchmark, the initial Ukraine supplemental (March 2022) was $13.6 billion. Interim funding might be combined with the Ukrainian aid package, giving the latter an extra push towards enactment. An additional amount for Israel could come later and during the regular budget cycle if more was needed.

Q5: So can the United States keep Israel supplied, given the other commitments, or is this beyond what even a superpower can do?

A5: The preceding discussion indicates that the answer is yes, but with some difficult tradeoffs later. Israel’s needs are likely to be relatively small compared to what Ukraine has needed. The forces involved are smaller, and the war will likely be shorter. Israel's relationship with the United States is closer and longer standing. Therefore, Israel will get priority. The initial ask—as currently reported—does not conflict with Ukraine’s or Taiwan’s needs. SDB is available in large numbers, and neither Ukraine nor Taiwan uses the Iron Dome.

Nevertheless, as time goes on, there will be trade-offs as certain key systems are diverted to Israel. A few systems that Ukraine needs for its counteroffensive may not be available in the numbers that Ukraine would like. This will not force an end to operations but might become noticeable on the front lines if the war in Gaza continues for an extended period.

Mark Cancian (Colonel, USMCR, ret.) is a senior adviser with the International Security Program at the Center for Strategic and International Studies in Washington, D.C.