Paul’s touchiness is more interesting than his argument. Noting that Reagan sometimes did dovish things does not weaken Cruz’s (obviously correct) contention that Reagan was more hawkish than Paul is. While Russia was planning to move into Crimea, Paul was warning that U.S. officials should not “tweak Russia all the time” and should instead “be respectful.” Other Republicans have not said anything similar, and it is difficult to imagine Reagan — who believed it was important to call out the Kremlin — saying it either.

So why doesn’t Paul just say that circumstances have changed since the 1980s and our policies should change, too? Why does he protest when someone points out the obvious?

I suspect Paul’s problem is simple: For all the talk of rising Republican isolationism, he knows full well that he is an outlier in his party.