There is little chance Assad will retaliate, says Jack Keane, a retired Army general who served as the service’s No. 2 officer from 1999 to 2003. “He wants our ships to go away,” Keane says, “and take their cruise missiles with them.”

But Iran is a different story. It won’t openly lash out against the U.S. or Israel, he predicts. “That would give [Israeli Prime Minister Benjamin] Netanyahu the excuse he needs to go get Iran’s nuclear weapons once and for all,” Keane says. “But they might do more state-sponsored terrorism using surrogates” like the Hizballah Shiite-militant group.

“They’ve been killing us for 30 years, and we’ve never lifted a finger against them,” he says, citing bombings across the region beginning with Beirut in 1983, to providing U.S. foes in Iraq with deadly explosively-formed penetrators that Keane estimates killed 1,200 U.S. troops. “So they could attack U.S. targets in the region,” he says. Then he pauses. “But the truth is,” he adds, “that could happen any time.”