The president had opposed Israeli action against Iran but came to believe that Israel had reason to act and that the U.S. would have to lend some support.

Israel and Iran both have little incentive to stop and no obvious route to outright victory. Much depends on President Trump.

Israel and Iran exchange airstrikes targeting military sites and nuclear facilities, with Trump comments on the conflict and expressing optimism for diplomatic resolution.

Former Vice President Mike Pence said on “State of the Union” Sunday that if Israel’s attack doesn’t somehow convince Iran to make major concessions in Trump’s diplomatic attempt to end its nuclear program, then the United States should be prepared to join the conflict.

Also looming over the meeting are President Trump's inflammatory threats to make Canada the 51st state and take over Greenland.

President Donald Trump said the United will come down on Iran “at levels never seen before” if the Middle Eastern country attacks.

Israel’s attack on Iran was long in the making – the result of years of meticulous planning by Israel and days of high-stakes talks between Tel Aviv and Washington, officials told CNN.