President Obama’s aides went to extraordinary lengths to uncover the identity of a senior official who was using Twitter to make snarky comments about White House staffers. Suspicion gradually centered on Jofi Joseph, the point man on nuclear nonproliferation at the National Security Council. So at a meeting in which everyone was in on the scam an inaccurate but innocuous news tidbit was revealed. When Joseph used his anonymous Twitter handle #natlsecwonk to broadcast the tidbit he was caught and promptly fired. He was not fired for revealing any secrets, but for making disparaging comments about thin-skinned administration players ranging...