In a new report, defense analyst William D. Hartung detailed how the United States has provided at least $21.7 billion in military aid to Israel since the start of the war in Gaza on Oct. 7, 2023. Published jointly by the Costs of War Project at Brown University and the Quincy Institute for Responsible Statecraft, the report argues that this aid — alongside tens of billions in future arms sales — has enabled Israel’s military campaign and regional escalation.
“Given the scale of current and future spending, it is clear the Israeli Defense Forces (IDF) could not have done the damage they have done in Gaza or escalated their military activities throughout the region without US financing, weapons, and political support,” Hartung wrote.
The report breaks down the $21.7 billion figure into several categories: $8.1 billion in Foreign Military Financing; $725 million in Offshore Procurement; $5 billion for missile defense systems; $4.4 billion to replenish US stockpiles used by Israel; $801 million for ammunition procurement; and $198 million to boost US arms production capacity
Hartung emphasized that these figures do not include future arms sales agreements, many of which will be paid for by additional appropriations. He noted that the Biden administration announced an $8 billion arms sale to Israel in January 2025, including Hellfire missiles, 155mm artillery shells, and 500-pound bombs. These systems are expected to be delivered over the coming years.
The report also cited a companion study by Linda J. Bilmes estimating that the US spent $9.65 to $12.07 billion on military operations in Yemen, Iran, and the wider region in support of Israel’s war effort. Combined, the total US expenditure reached $31.35 to $33.77 billion across two years.
Hartung described the Israeli military’s reliance on US weapons as extensive and decisive.
“Israel’s entire inventory of combat capable aircraft comes from the US, including 75 F-15s, 196 F-16s, and 39 F-35s,” he wrote. “Israel’s attack and transport helicopters are also all of US origin, including 46 Apache helicopters and 25 Sea Stallion and 49 Black Hawk transport helicopters.”
The report added that these platforms, along with tens of thousands of US-supplied bombs and missiles, have inflicted a devastating toll on Gaza.
“Over 60,000 Palestinians have died from direct Israeli military attacks, with tens of thousands more dying from starvation and preventable diseases provoked by the Israeli military’s brutal assault on Gaza.”
Hartung cited multiple sources, including Gaza’s Health Ministry, Israeli human rights organizations, and the United Nations High Commissioner for Human Rights, which have described the situation as genocidal.
The report also examined the mechanics of arms transfers. Hartung explained that the weapons flow through two primary channels: Foreign Military Sales (FMS), which are brokered by the US government, and Direct Commercial Sales (DCS), which are licensed by the State Department and negotiated by private companies. He noted that major arms sales must be notified to Congress, but rarely face successful opposition.
Since Trump took office in January 2025, the administration has notified Congress of at least $10.1 billion in new arms sales to Israel, including thousands of bombs, JDAM guidance kits, Hellfire missiles, and Caterpillar bulldozers.
“The major offers announced by the Trump administration in February 2025 were largely negotiated during the waning weeks of the Biden administration, but only notified to Congress after the Trump administration took office,” the report said.
He also reported that Trump lifted a suspension on the delivery of Mark 84 and BLU-109 bombs, which had been delayed by Biden due to concerns about civilian harm. Additionally, Trump reinstated the delivery of 20,000 assault rifles that had been held back over fears they might be used by Israeli settlers.
Opposition to US arms transfers to Israel has grown in Congress. Hartung noted that Senator Bernie Sanders forced three votes of disapproval, one of which garnered majority support among Senate Democrats. He also cited Republican Representative Marjorie Taylor Greene, who called Israeli actions in Gaza a genocide.
Looking ahead, Hartung warned that negotiations over the next 10-year Memorandum of Understanding (MoU) on US military aid to Israel are likely to begin soon. The current MoU, signed under Obama, guarantees $3.8 billion annually through 2028.
Hartung urged transparency and public input: “The next MoU should be negotiated in the full light of day with meaningful input from Congress and the US public.”