The United States has spent an unprecedented $17.9 billion in military aid to Israel since the Gaza war began on October 7, 2023, according to a comprehensive report from Brown University’s Costs of War project. This marked the highest amount of U.S. military aid sent to Israel in a single year. As the conflict escalates, the repercussions are being felt across the Middle East, with Iran-backed groups like Hezbollah and the Houthis joining the fray, forcing the U.S. to bolster its military presence in the region at additional costs.
The war between Israel and Hamas erupted on October 7, 2023, when Hamas militants launched a surprise attack, breaching Israeli barricades and killing over 1,200 people, with many others taken hostage. Israel swiftly retaliated with intense airstrikes and a ground offensive in Gaza. According to the Gaza Health Ministry, the conflict has since claimed the lives of nearly 42,000 people in Gaza. This toll includes both combatants and civilians, though the distinction between them remains unclear in official reports.
The escalating violence has drawn the attention and involvement of the United States, which has long been Israel’s most prominent military ally. Historically, Israel has been the largest recipient of U.S. military aid, receiving a staggering $251.2 billion (in inflation-adjusted dollars) since 1959. But the record-breaking $17.9 billion in military support allocated since October 2023 underscores the depth of U.S. commitment to Israel’s security during this new wave of hostilities.
The report from Brown University, compiled by experts Linda J. Bilmes, William D. Hartung, and Stephen Semler, offers a granular look into the U.S.’s financial investment in this conflict. The aid includes a mixture of foreign military financing, direct arms sales, and the drawdown of U.S. military stockpiles. A substantial portion of the assistance, amounting to at least $4.4 billion, came from U.S. reserves of munitions, which included artillery shells, bunker-busting bombs, and other precision-guided weaponry.
One of the most significant categories of expenditure has been to replenish Israel’s missile defense systems. The Iron Dome, Israel’s most iconic missile defense system, and David’s Sling, a similar defensive network, received a total of $4 billion in U.S. funding. These systems have played a crucial role in protecting Israeli cities and military installations from Hamas and Hezbollah rocket attacks.
In addition to replenishing defense stockpiles, the U.S. provided Israel with financing for the procurement of rifles, military vehicles, and aircraft fuel to sustain its operations. Notably, the report points out that unlike the transparent disclosures of U.S. military assistance to Ukraine during its conflict with Russia, the full details of aid provided to Israel since October 2023 remain opaque. Researchers attribute this lack of transparency to what they describe as “bureaucratic maneuvering” by the Biden administration to obscure the true scale of military support.
Alongside the direct financial aid to Israel, the U.S. has significantly ramped up its military presence in the Middle East. According to the Brown University report, the U.S. has spent an additional $4.86 billion on stepped-up operations in the region since the war began. This figure includes the costs of deploying two aircraft carriers, fighter jets, destroyers, and amphibious assault groups to strategic locations in the Mediterranean Sea, Red Sea, and Gulf of Aden. The U.S. has sought to deter attacks on its forces and Israeli targets, as well as to respond to increasing hostilities by Iranian-backed militias across the region.
The conflict has spilled over into neighboring Lebanon, where Israeli strikes have targeted Hezbollah, a militant group supported by Iran. Since Israel intensified its airstrikes in late September, at least 1,400 people have been killed in Lebanon, including Hezbollah fighters and civilians. The escalating violence on this second front adds another dimension to the already complex geopolitical situation.
Iran’s involvement in the conflict has drawn U.S. attention to allied forces across the region. Most notably, the Houthi militias in Yemen, who are aligned with Iran and Hamas, have increased attacks on commercial shipping in the Red Sea, disrupting vital trade routes. The U.S. Navy, as part of its broader mission to safeguard maritime security, has launched several operations to neutralize Houthi missile launch sites and drones, further complicating U.S. military engagement in the region.
One of the lesser-reported consequences of the U.S.’s expanded military role in the Middle East has been the intensification of maritime conflict with the Houthi militias. Researchers from the Costs of War project described the ongoing naval battle in the Red Sea as the most intense sea warfare the U.S. Navy has faced since World War II.
The Houthis, who control large portions of northern Yemen, have repeatedly targeted merchant vessels with cheap Iranian-made drones and missiles. The U.S. military, in response, has deployed advanced weaponry, including multimillion-dollar guided missiles, to intercept these relatively low-cost threats. Despite the technological superiority of U.S. forces, the asymmetric nature of the conflict has proven to be a costly and ongoing challenge. To date, the U.S. has spent $4.86 billion on these operations, an expenditure that includes the maintenance of naval assets, aerial surveillance, and missile defense operations.
Just last week, the U.S. military struck more than a dozen Houthi targets in Yemen, going after weapons systems, drone launchers, and other military infrastructure. The strategic goal of these strikes has been to disrupt the Houthis’ ability to threaten critical trade routes and maintain the safety of commercial shipping.
While the financial expenditures related to the conflict are vast, the human toll is equally significant. As of this report’s release, thousands of civilians have died on both sides of the conflict. Human rights organizations and global leaders have expressed concern about the humanitarian situation in Gaza, where ongoing Israeli airstrikes have destroyed infrastructure and displaced large swaths of the population. The Biden administration, for its part, has reaffirmed its support for Israel’s right to defend itself but has also called for efforts to mitigate civilian casualties and provide humanitarian aid to Gaza.
Domestically, the U.S. support for Israel’s military campaign has become a divisive issue in the lead-up to the 2024 presidential election. Many progressive Democrats have expressed discomfort with the level of military aid sent to Israel, especially in light of the civilian death toll in Gaza. On the other hand, Republicans and more moderate Democrats have largely backed the Biden administration’s stance, arguing that the U.S. must stand firm with its closest ally in the region. President Joe Biden has maintained that “no administration has helped Israel more than I have,” emphasizing his long-standing support for the country’s defense.
At the same time, the presence of U.S. troops in the region — which swelled from 34,000 at the time of the initial Hamas attacks to around 50,000 during the peak of operations — has sparked concerns of mission creep. As the conflict drags on and the U.S. continues to face new challenges, like the ongoing naval battle with the Houthis, some lawmakers have raised concerns about the potential for the U.S. to become more deeply entangled in a broader Middle Eastern war.
The U.S. has committed a staggering $17.9 billion in military aid to Israel since the war in Gaza erupted, with additional billions spent to bolster U.S. military operations across the Middle East. As the conflict widens to involve Iran-backed groups in Lebanon and Yemen, the financial and human costs continue to mount. For the Biden administration, the stakes are high, both in terms of foreign policy and domestic political ramifications. While U.S. aid and military involvement are likely to continue, the long-term consequences of this unprecedented financial and military investment remain to be seen.
