The closure of airspace over Iran and Israel has severely impacted air travel through the region, grounding flights and stranding travellers.

But behind the scenes, the president already knew an attack on Iran could be imminent - and that there might be little he could do to stop it, according to two U.S. officials. By mid-May, the Pentagon had begun drawing up detailed contingency plans to aid Israel if it followed through on its long-held ambition to strike Iran's nuclear program,