Leon Panetta: “I think this has been a probably the most disastrous foreign policy blunder in recent history.”

And that is the danger here: that rather than bringing peace, it's going to bring more war.

The answer is no, not at all. Not in 100 years. These plans that the Pentagon develops, we -- we develop these plans to deal with every potential crisis that's out there.

Mr. Trump has always prided himself on being a dealmaker, pledging in his campaign that he would resolve such conflicts in the first few days of his presidency.

The president, as commander in chief, has the power and responsibility to determine America’s future security.