Drones aren’t the biggest issue for me, but I’m glad Rand Paul made a big stink about them. I agree with Josh Barro that even if it’s not a slippery slope, it’s public fights that keep the slope unslippery.
The notion that this indicates some change in the Republican mindset on foreign policy is silly, though. There’s always been an isolationist contingent within the party, as is evidenced by Rand’s father’s strong showings in primaries. I’ll admit that the Paul Père et Fils do seem to do especially among younger voters, and that may mean something, but when the chips are down, most of the party will be happy to whip itself into a frenzy against whoever their overlords decide is the Hitler of the month. Right now, Obama is a bigger Hitler than whatever Hitler the drones might be fighting against.
You go to war against the Hitler you have, not the Hitler you wish you had.