The terror group that’s taken over major portions of Iraq and Syria won’t be content with roiling those two countries, senior Obama administration officials told Senators in a classified briefing this week. The Islamic State of Iraq and al-Sham (ISIS) also has its eyes on Jordan; in fact, its jihadists are already Tweeting out photos and messages claiming a key southern town in Jordan already belongs to them.

An ISIS attack on Jordan could make an already complex conflict nightmarishly tangled, the officials added in their briefing. If the Jordanians are seriously threatened by ISIS, they would almost certainly try to enlist Israel and the United States into the war now engulfing the Middle East.

“The concern was that Jordan could not repel a full assault from ISIS on its own at this point,” said one senator, who spoke on condition of anonymity. Another Senate staff member said the U.S. officials who briefed the members responded to the question of what Jordan’s leaders would do if they faced a military onslaught from ISIS by saying: “They will ask Israel and the United States for as much help as they can get.” […]