INSIGHTi
Escalation of the Israel-Iran Conflict
Updated April 22, 2024
Overview
A series of strikes and counter-strikes between Israel and Iran in April 2024, including the first-ever direct
attack on Israel from Iranian soil, represents a significant escalation in a years-long “shadow war”
between the two countries. 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.
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.”
One week after Iran’s direct attack on Israel, and one day after an apparent Israeli strike in Iran that may
have been sufficiently narrow in scope to avoid additional immediate escalation, the House passed
legislation that would appropriate additional U.S. military assistance to Israel (along with global
humanitarian aid partly for Gaza), as well as direct the imposition of additional sanctions on Iran.
Iran’s Direct Attack on Israel
On April 13, Iran initiated the first-ever direct military action against Israel from Iranian territory in the
form of aerial attacks (drones and ballistic and cruise missiles). 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).
In total, Iran and allied groups reportedly launched approximately 350 drones and missiles from Iran,
Syria, 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
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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.
U.S. officials contend that Iran, given the scale of the attack, was seeking to cause “significant destruction
and casualties,” explicitly arguing against analysis that “the Iranians meant to fail.” Those who align with
that latter viewpoint contend that Iran could have used more drones and missiles and/or more advanced
variants, and that Iran “did telegraph these attacks in advance which made them easier to deter.” In any
event, Iran’s demonstrated ability and willingness to launch missiles and drones directly at Israel marks a
watershed in the two nations’ conflict. Iranian military officials have said that the attack creates a “new
equation,” with the IRGC commander stating, “From now on, if Israel attacks Iranian interests, figures
and citizens anywhere, we will retaliate from Iran.”
Reactions and Subsequent Developments
Many Western countries denounced Iran’s attack and a broader group of world leaders called for regional
de-escalation. President Biden sought to “coordinate a united diplomatic response to Iran’s brazen attack”
while pledging to remain engaged with Israel and other regional counterparts. On April 18, President
Biden announced additional U.S. sanctions targeting the IRGC and entities supporting Iran’s drone
programs, and stated that U.S. “allies and partners have or will issue additional sanctions and measures to
restrict Iran’s destabilizing military programs.” Israeli officials reportedly considered a range of responses
to the April 13 attack, after 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.”
On April 19, Israel reportedly launched an air attack near an Iranian military base in the central province
of Isfahan, and supposedly provided a few hours’ advance notice to U.S. officials. Although the attack
appeared to be relatively narrow in scope, it may have signaled an Israeli ability to evade and target
Iranian air defenses—apparently damaging the radar on a Russian-origin S-300 system—in a province
where some of Iran’s nuclear facilities are located. Iranian leaders downplayed the strike’s impact while
reiterating pledges to retaliate against any “proven” and “decisive” Israeli action against Iran. The muted
response from Iran, the relatively limited scope of the strike, and the lack of official U.S. or Israeli
comment on the incident led many observers to conclude that the situation may have de-escalated for the
time being. Nevertheless, heightened risks of direct Israel-Iran conflict may persist, with Israel likely to
continue efforts to disrupt Iranian support for groups Israel deems as threats.
Issues for Congress
Israel-Iran clashes 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.
On April 20, the House passed four bills, including two related to the Middle East. H.R. 8034 would
provide approximately $14 billion in Israel-related supplemental appropriations and $9 billion in global
humanitarian assistance funding. H.R. 8038 would, among other provisions, direct the President to
impose a number of sanctions related to various Iranian activities, including its petroleum exports, its
missile programs, and its human rights violations. President Biden hailed passage of the four bills, and
urged the Senate to “quickly send this package to my desk.”
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Author Information
Clayton Thomas
Jeremy M. Sharp
Specialist in Middle Eastern Affairs
Specialist in Middle Eastern Affairs
Jim Zanotti
Specialist in Middle Eastern Affairs
Disclaimer
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