Tensions between Iran and the U.S. have shaped the Middle East for decades, revolving around Iran's nuclear program, regional influence, and recurring diplomatic crises. In recent weeks, the situation has escalated to its highest point.

After years of sanctions, covert operations, and periodic negotiations since 1979, the signing of the Joint Comprehensive Plan of Action (JCPOA) in 2015 represented a rare opportunity for de-escalation and rapprochement. What follows is a timeline of key events from that moment through early 2026, highlighting the ebb and flow of diplomacy, sanctions, military confrontations, and domestic unrest that have defined U.S.-Iran relations.

Here are is the timeline of the escalating U.S.-Iran tensions since 2015.

Timeline: Escalating U.S.-Iran tensions since 2015