Fracture?

Michael Isikoff has this quote in his Newsweek article about Bush's 'deliberations' about commuting/pardoning Scooter Libby.

Cheney did not directly weigh in with Fielding, but nobody involved had any doubt where he stood. "I'm not sure Bush had a choice," says one of the advisers. "If he didn't act, it would have caused a fracture with the vice president."

What is the hold that Cheney has on Feckless Leader? Sure, Bush is intellectually negligible, he has no interest in actually governing, and if Cheney hadn't fucked everything up so badly he would have had good reason to ride out the end of his term in quiet uselessness. But that is not the current situation, the wars are going south, the Republicans are flipping out, and Cheney is still pushing for another war. Is that why Gates just canceled his Latin America trip? Is he a counterweight to Cheney in foreign policy and able to fortify Bush to resist Cheney? Condi isn't and never has been, but then, neither was Powell.

So what would a fracture mean?