But now there’s no negotiation, although there might conceivably be some progress Monday night. But the fact is that Republicans blame Reid for running the Senate in a particularly abusive way, twisting the Senate’s rules to limit the minority’s ability to offer amendments and setting off cloture fights on even relatively routine matters. Democrats, of course, accuse Republicans of bringing the Senate to a halt.

Cornyn realizes the majority has the power to make the change, if it wants. “No one denies that as a practical matter it’s possible to do so,” he says. “What people are reluctant to do is start down a slippery slope where you do this on executive nominations, and then it goes to judicial nominations, and then to regular legislation.” If that were to happen, the filibuster, which in the past has been used to stop both good legislation and bad, would be gone.

And that would probably bring on a wave of Republican reprisals. They don’t call it the “nuclear option” for nothing — Reid’s action would likely set off a nuclear winter inside the Senate that might last for a very long time. It’s the kind of thing that, in the past, called for cooler heads to find a solution. This time, however, that might not happen. “It doesn’t feel like that right now,” says Cornyn. “It feels like Reid has escalated this thing to a point where it’s hard to see him going backward.”