Even though his filibuster against Obamacare is no proof that Ted Cruz is a real conservative, he deserves much credit for doing what he did. And his Republican opponents are equally deserving of criticism, for their response to Cruz’s “red line”—and to be sure, Cruz did indeed draw the proverbial red line—is most certainly proof that they are not the conservatives who they claim to be. First, it is “limited government,” and the individual liberty that this entails, for which Republicans are supposed to stand. Obamacare, though, is perhaps the most glaring affront to limited government and individual liberty that...