The United States attributes the worsening of relations to the 1979–81 Iran hostage crisis, Iran's repeated human rights abuses since the Islamic Revolution, different restrictions on using spy methods on democratic revolutions by the US, its anti-Western ideology and its nuclear program.

During the Iran–Israel war, by 24 June 2025, Human Rights Activists in Iran (HRANA), a US-based organization, reported that over 900 people have been killed and over three thousand wounded by Israeli strikes on Iran. The Iranian health ministry stated that more than 4,000 people have been wounded.

Iran is not known to currently possess weapons of mass destruction (WMD) and has signed treaties repudiating the possession of WMD including the Biological Weapons Convention (BWC), the Chemical Weapons Convention (CWC), and the Non-Proliferation Treaty (NPT).