The Rule of Law
Some on the hard right would have you believe that checking the executive's power is somehow a left-liberal project. It may be; but it's also a project that many conservatives, worried about an unnecessarily intrusive government, should be deeply involved in. I favor aggressive attempts to hunt down our enemy; I'd be fine with NSA wiretapping with warrants; I'd be in favor of re-vamping FISA to make it compatible with modern technology. The choice is not, in other words, between doctrinaire civil libertarians and hard-ass terrorist-hunters. It's between providing a sliver of accountability and providing none. Mercifully, plenty in the administration recognized this. Predictably, they've all been purged.