In my conversations with experts, five potential Iranian moves kept surfacing. Iran could take a big step and use its military to disrupt shipping or even seek to shut down commerce in the Strait of Hormuz, a crowded international waterway near southern Iran through which roughly one-fifth of the world’s oil supply passes.

In a briefing at the Pentagon, officials said the U.S. strikes caused “severe damage” to Iranian nuclear sites. Iran condemned the attacks and has vowed to defend itself.

President Trump says the U.S. military struck three sites in Iran, inserting itself into Israel's effort to decapitate the country's nuclear program in a risky gambit.