Killing Khamenei? Hitting military sites? It is unclear what a US attack on Iran would achieve | Dan Sabbagh

Trump now has the firepower in place, but using it might not end well

A fortnight ago, when Donald Trump first threatened Iran's regime, telling protesters in the country that help is coming", there were not enough US military assets in the Middle East to back up the rhetoric. That has now changed, although plenty of questions remain about what an attack on Iran could achieve.

An aircraft carrier, the USS Abraham Lincoln, has arrived in the Indian Ocean, dispatched from the South China Sea alongside three destroyers equipped with Tomahawk cruise missiles. Its eight-squadron air wing includes F-35C and F/A-18 jets and, critically, EA-18G Growlers to suppress anything that is left of Iran's air defences after last year's war with Israel.