The operation targeted nuclear facilities, military sites, and regime infrastructure in Iran. It killed several top military leaders—most notably Hossein Salami, the head of the Islamic Revolutionary Guard Corps (IRGC), and Mohammed Bagheri, the chief of staff of the armed forces—as well as several nuclear scientists.

The Joint Comprehensive Plan of Action (JCPOA) was a 2015 agreement that limited Iran’s nuclear program in exchange for relief from international sanctions. Many experts concur that it would have delayed Iran’s ability to develop a nuclear weapon by at least a decade, but the United States pulled out of the deal in 2018, and Iran began reneging on it in 2019.

The United States struck Iran after years of rising tension over Iran’s nuclear program, its ballistic missiles, and its reach in the Middle East. Although an agreement to restrain Iran’s nuclear program was concluded in 2015 (see Joint Comprehensive Plan of Action [JCPOA]), the United States withdrew from that agreement in 2018 after Pres. Donald Trump said that it did not address enough of the outstanding issues. Attempts to negotiate a new agreement began in 2025 and again in 2026, but those attempts did not succeed. A factor in the negotiations and in the decision to strike were Iran’s weakened position due to the Israel-Hamas War, the 12-Day War in June 2025, and the 2026 Iranian protests. For more, see 2026 Iran conflict.