The map created using a simulation tool shows the devastating impact of a hypothetical U.S. nuclear strike on Tehran, Isfahan, and Qom.

Nine countries currently either say they have nuclear weapons or are believed to possess them. The first to have nuclear arms were the five original nuclear weapons states — the United States, Russia, China, France and the United Kingdom.

President Trump said Monday that he disagrees with Director of National Intelligence Tulsi Gabbard's assessment from a few months ago that Iran is not currently trying to build a nuclear weapon and has not been doing so since 2003.