In an uncompromising address at the White House, Mr Trump said Iran’s nuclear programme had been “completely and totally obliterated”. That is an overstatement: Iran has decades of accumulated expertise that is hard to eliminate.

Saturday’s U.S. strike on Iranian targets “was the easy part… once you’ve got a toe in the water, you’ve got a foot in the water and then you’re all the way in,” a foreign policy analyst told HuffPost.

By Matt Spetalnick WASHINGTON (Reuters) -With his unprecedented decision to bomb Iran’s nuclear sites, directly joining Israel’s air attack on its regional arch-foe, U.S. President Donald Trump has done something he had long vowed to avoid - intervene militarily in a major foreign war.