#IsraelIranConflict Iran trained and armed Hezbollah during Israel's 1982 invasion of Lebanon, and continued to back Shia militias throughout the Israeli occupation of Southern Lebanon.[24] Even before 1979, Iranian Islamists had materially supported the Palestinians; after 1979 Iran attempted relations with the Palestine Liberation Organization, and later with Palestinian Islamic Jihad and Hamas. Israel fought a war with Hezbollah in 2006.

Israel has fought several wars with Palestinians in and around the Gaza Strip: in 2008–2009, 2012, 2014, 2021 and 2023–2024. The 1982 Lebanon War and Gaza war have been the deadliest wars of the Arab–Israeli conflict.[25] In the Israeli–Lebanese conflict, Iran has supported Lebanese Shia militias, most notably Hezbollah. In the Israeli–Palestinian conflict, Iran has backed Palestinian groups such as Hamas. Israel has received military support from the United States, as well as Germany, Britain, and Italy.[26][27][28][29] Israel has also conducted airstrikes against Iranian allies in Syria and has been suspected of assassinating Iranian nuclear scientists. In 2018, Israeli forces directly attacked Iranian forces in Syria.[30]

Various reasons have been given for the Iran-Israel conflict. Iran and Israel had previously enjoyed warm ties due to common threats, but by the 1990s the USSR had dissolved and Iraq had been weakened.[31] Iranian Islamists have long championed the Palestinian people, whom they perceive as oppressed.[32] Scholars believe that by supporting the Palestinians, Iran seeks greater acceptance among Sunnis and Arabs, both of whom dominate the Middle East.[33][34] At times, Iran has supported the one-state and the two-state solution as a response to the plight of Palestinians,[35] while the country has also used more inflammatory language to predict Israel's demise.[36] Israel sees Iran as an existential threat,[37] and accuses its regime of harboring genocidal intentions.[38] Consequently, Israel has sought sanctions and military action against Iran to stop it from acquiring nuclear weapons.[39]