Alternate headline: “New Ron Paul ready to take on old Ron Paul.” He’s pro-gay-marriage, pro-legalization of marijuana, pro-choice (which Paul is not), and very, very pro-veto when it comes to new spending bills. He’s the great libertarian hope, in other words — or he would be, if not for the fact that the other great libertarian hope is probably also running next year. And even if Paul pere ends up passing, Paul fils might well end up taking his place. I wish all three would run, if only because the debates would be enormously entertaining. Who’s the laissez fairest of them all?

More seriously, I’m glad Johnson’s running because I’m curious to see what the high-water mark of libertarianism is in the GOP at a moment when everything seems to be breaking its way. National opposition to gay marriage is gradually softening; our ill-conceived intervention in Libya plus 10 years of war fatigue has made isolationism more viable than it was recently; and of course, fiscal discipline as an antidote to Obamanomics and our crushing national debt has become the party’s core value. If, after decades of gestating in Hollywood, the “Atlas Shrugged” movie can now safely be delivered by the zeitgeist, it must be an omen of something. And yet … it probably isn’t. My guess is that Johnson will be pigeonholed by the media early on as the “weed” candidate and that RINO-y types who might find his moderation on social issues appealing will balk on the assumption that the southern base wouldn’t turn out for him in the numbers needed to beat Obama. I don’t think the party’s turned isolationist either: You’re much, much more likely to hear Republicans complain that Obama’s too weak internationally than that he’s too aggressive, which would also be a knock on a dovish candidate like Johnson. Even so, it’ll be fun having him at the debates clashing with Romney, Palin, and maybe even John Bolton. Good bloggy content, if nothing else.

Two clips here, the first via RCP of this morning’s announcement and the second of an interview he did last year with Matt Welch and Nick Gillespie of Reason.