INSIGHTi
Escalation of the Israel-Iran Conflict
April 13, 2024
Overview
On April 13, the Islamic Republic of Iran, for the first time, initiated a kinetic military action against
Israel in the form of aerial attacks (drones and ballistic and cruise missiles) launched from Iranian
territory toward the state of Israel. Iran states that the attacks were in retaliation for an April 1 strike
reportedly by Israel against a building within the Iranian embassy compound in Damascus, Syria. That
strike killed high-level members of the Islamic Revolutionary Guard Corps (IRGC), an arm of the Iranian
military and a U.S.-designated Foreign Terrorist Organization (FTO). Israeli, U.S., and other partner
forces shot down “nearly all” of the projectiles, which caused minor damage in Israel. Israel’s war cabinet
has indicated that it is in favor of a response, but members reportedly disagree over the scope and timing,
as the United States seeks to de-escalate tensions.
This sequence of strikes and counter-strikes represents a significant escalation in a years-long “shadow
war” between Israel and Iran. Until now, the conflict had been fought mostly in theaters outside of each
country’s territory, between Israel and Iran-supported groups (such as Hezbollah in Lebanon), and/or by
covert or non-kinetic means (such as cyberwarfare). Israel-Iran escalatory attacks also come at a time
when Israel faces international pressure to reduce the impact of conflict on the Palestinian population in
Gaza, where Israel and Hamas (an Iran-supported group and FTO) have been engaged in warfare since
Hamas-led attacks against Israel on October 7, 2023.
The Biden Administration has pursued multiple lines of effort in responding to this latest crisis in the
Middle East. Despite weeks-long U.S.-Israel tensions over Israel’s conduct of the war in Gaza, U.S.
officials have communicated “full U.S. support to defend Israel against any attacks by Iran and its
regional proxies.” On April 12, amidst heightened Iranian threats to Israel, President Biden ordered the
repositioning of two guided missile destroyers, one armed with an Aegis missile defense system.
Diplomatically, U.S. officials have reportedly reached out to regional counterparts to encourage de-
escalation. At the same time, U.S. officials have expressed concern to Israeli counterparts that Israel did
not forewarn the United States before the April 1 Damascus strike. Since October 7, U.S. forces in the
Middle East have taken action to counter Iranian-backed armed groups in Iraq, Syria, and Yemen.
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The Events of April 13-14
On April 12, media, citing unnamed U.S. intelligence sources, reported that an Iranian strike on Israel
would occur within the next 24-48 hours. Other reports indicated that Iran’s response would be
“calibrated.” Early on April 13, IRGC forces boarded and seized an Israeli-linked, Portuguese-flagged
commercial ship in the Strait of Hormuz, commandeering the vessel and its 25 crew members. Since
2019, Iran has seized several ships—some with ties to Israel.
In the early hours of April 14, Iran and allied groups reportedly launched approximately 350 drones and
missiles from Iran, Lebanon, Iraq, and Yemen toward Israel. Israel had already mobilized its air defense
reserves, canceled schools, and closed its airspace. Once Iranian projectiles were airborne, Israel, along
with the United States, Jordan, France, and the United Kingdom, reportedly intercepted most of them,
using an array of combat aircraft and missile defense systems. The Israel Defense Forces said that nearly
all the estimated 350 drones and missiles fired were downed outside Israeli airspace by Israel and its
partners or were intercepted by Israel’s Arrow missile defense system. One Israeli base in the southern
Negev desert reportedly sustained minor damage, and one injury was reported.
As many Western countries have denounced Iran’s attack and a broader group of world leaders have
called for regional de-escalation, President Biden has convened the G7 in an effort to “coordinate a united
diplomatic response to Iran’s brazen attack,” while pledging to remain engaged with Israel and other
regional counterparts. Iran’s mission to the United Nations said, “The matter can be deemed concluded,”
while Iranian military leaders have warned that Israel would face a larger attack if it retaliates, and that
U.S. bases would be targeted if Washington backs any such retaliation. Reportedly, President Biden told
Israeli Prime Minister Benjamin Netanyahu “that the U.S. will not participate in any offensive operations
against Iran and will not support such operations.” The Israeli government is reportedly considering a
range of kinetic and other responses to the April 14 attack. On April 14, Israel did strike various
Hezbollah sites in Lebanon in response to some 40 rockets fired by Hezbollah at Israeli targets amid the
Iranian attack.
Issues for Congress
Iran’s attacks against Israel come at a time of congressional debate over U.S. support for Israel. In recent
months, including after an Israeli drone strike in Gaza that killed aid workers from the private World
Central Kitchen organization, some lawmakers have scrutinized U.S. arms sales to Israel and called for
either conditioning, restricting, or halting security assistance to Israel. Other Members have rejected calls
for conditioning U.S. aid to Israel and have criticized the Administration for pressuring the Israeli
government amid ongoing hostilities against Hamas and Hezbollah
Overall, Congress and successive administrations have demonstrated strong support for joint U.S.-Israeli
defense projects designed to counter aerial threats, including those emanating from Iran. Under the
current 10-year Memorandum of Understanding on military aid, the United States has pledged, subject to
congressional appropriation, to provide $500 million per year in missile defense programs to Israel. Last
month, Congress passed P.L. 118-47, the Further Consolidated Appropriations Act, 2024, which included
the $500 million (Section 8072) for various air defense systems, such as Arrow.
In the coming days, Congress may use the occasion of Iran’s strikes against Israel to resume consideration
of supplemental appropriations for Israel requested by President Biden in October 2023. Threats of
additional escalation with the potential to involve U.S. forces in the region could trigger broader
congressional consideration of U.S. diplomatic and military options. The President seeks over $14 billion
in Israel-related funding. On February 13, 2024, the Senate passed, via a substitute amendment (by a vote
of 70-29), H.R. 815, a bill that would provide $14.1 billion in Israel-related supplemental appropriations.
In the House, H.R. 7372, the Defending Borders, Defending Democracies Act, would provide $10.7
billion in Israel-related appropriations (though no Foreign Military Financing).
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Author Information
Jeremy M. Sharp, Coordinator
Jim Zanotti
Specialist in Middle Eastern Affairs
Specialist in Middle Eastern Affairs
Clayton Thomas
Specialist in Middle Eastern Affairs
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