Israel's role in the Iran–Iraq war  Israel's role in the Iran–Iraq war refers to support provided by Israel to Iran during the Iran–Iraq War from 1980 to 1988. During the war, Israel was one of the main suppliers of military equipment to Iran. Israel also provided military instructors during the war and direct support to Iran's war effort, when it bombed and destroyed Iraq's Osirak nuclear reactor, during Operation Opera. The nuclear reactor was a central component of Iraq's nuclear weapons program. Israel supported Iran during the war so that Iran could provide a counterweight to Iraq; to re-establish influence in Iran which Israel lost with the overthrow of the shah in 1979; and to create business for the Israeli weapons industry. The Israeli arms sales to Iran also facilitated the unhindered immigration of the Persian Jewish community from Iran to Israel and the United States. Israel's support for Iran during the war was done clandestinely, and Iran publicly denied any cooperation between the two countries. Before the Iranian Revolution in 1979, Iran under the Shah Mohammad Reza Pahlavi was an ally and major buyer of Israeli weapons. However, after the revolution, the new government of Ayatollah Khomeini, froze relations with Israel and was openly hostile towards it. Relations between Iran and Iraq also deteriorated after the revolution. Khomeini preached to Iran's bordering Shiite populations to continue the Islamic revolution. Iran actively sought to destabilize its neighboring countries seeking regional hegemony, even though neighboring countries like Iraq sought a conciliatory position. Iran's hostility led to an escalation of rhetoric between Ayatollah Khomeini and Iraqi President Saddam Hussein, a Sunni who advocated for secular pan-Arab nationalism. With the turmoil in Iran, because of the revolution, Saddam Hussein saw an opening to take Iran's Khuzestan province which had Iran's southern oilfields and an Arab majority. By early 1980, it became evident to both countries that preparation for possible war would be a necessary measure. The first prime minister appointed by the revolutionary government was Mehdi Bazargan. He reached out to the U.S. government for military arms to help consolidate his position; however, the Carter administration chose not to become involved in Iran's internal affairs. By the fall of 1979, Prime Minister Bazargan's moderate faction began to lose the internal struggle to the rising extremist faction in the revolutionary government. On 4 November 1979, elements of the extremist faction seized the United States embassy and held the American embassy employees hostage. As a result of the hostage taking, the US government placed an embargo on Iran.