Regime change in Iran could be a result of Israel's military attacks on the country, Israeli Prime Minister Benjamin Netanyahu told Fox News on Sunday, saying Israel would do whatever is necessary to remove the "existential threat" posed by Tehran.

Iran has vowed to retaliate against the U.S., too, while Trump has warned: “If we are attacked in any way, shape, or form by Iran, the full strength and might of the U.S. Armed Forces will come down on you at levels never seen before.” Here’s what to know about U.S. involvement so far.