Rand Paul's endorsement of Mitt Romney is understandable, predictable, and pragmatic-- for Rand Paul.

On the one hand, this move looks like an unconscionable sell-out. How could the son of Ron Paul, the most independent and intellectually consistent candidate for president, actually endorse the most philosophically empty and opportunistic candidate? But on the other hand, Paul is merely fulfilling a vow he made at the beginning of the presidential campaign: to support the eventual nominee.

It was but a few months ago that Republican talking heads were demanding to know if Ron Paul would endorse the eventual nominee and concretely rule out a third party run. If Ron Paul didn't agree to these ad hoc terms it was implicated that son Rand would be marked by his own party for political extinction. The same issue is in play with Rand Paul's endorsement.

Rand Paul's actual endorsement is itself rather weak. The younger Paul blathers about Romney's intention to audit the Federal Reserve and preserve internet freedom but his explanation seems contorted and forced. Even when talking about the personal reasons to support Romney it sounds like Rand Paul is bluffing his way through an oral exam:

"Governor Romney and I actually have quite a few similarities. Governor Romney's dad ran for president, was unsuccessful, Governor Romney then went on to support the nominee the same way his dad did. Governor Romney comes from a big family, I don't even know them that well but I think it's a big loving family, so do I, I come from a family with five kids, Governor Romney has five kids. He's had a long and happy marriage, so have my parents. I think we have a lot of the same family values."

This endorsement is disappointing for the more passionate and independent of Ron Paul's supporters but he isn't the first member of his wing of the GOP to choose party unity and pragmatism over principle.

Except in 2000 when he ran third party, Pat Buchanan always supported the nominee, including George W. Bush in 2004. And although he's still highly regarded in Old Right circles, "Mr. Republican" Robert Taft rallied his supporters around Tom Dewey and Dwight Eisenhower. The results have been mixed, so there is no guarantee for Rand Paul, but the reasons were the same: staying loyal to the party in order to have a place to fight for their ideas another day. From the perspective of a young senator it may be a small gamble to support an undesirable nominee today in exchange for goodwill down the road should he decide to wage his own campaign for the White House.

As Daniel McCarthy, editor of The American Conservative notes:

"The . . . strategy which Buchanan adopted now and Rand seems to be testing, is to be loyal to the party while establishing yourself as one of its philosophical poles: Buchanan was the party's social conservative pole in the 1990s, and Rand has a strong claim to being the constitutionalist pole today. The advantage here is that regular Republicans are open to your message - hence Buchanan could win the 1996 New Hampshire primary - but part of the price to paid is support for the party's nominee."

Rand Paul is young and has chosen to play the long game. As Otto von Bismarck said, "Politics is the art of the possible" and that means maintaining a balance between principles and pragmatism. The trouble is realizing where the balance lies, where it is wise to bend and when it is time to make a Spartan Stand. Rand Paul's record in the senate has not been perfect but it's not terribly objectionable.

If a freshman senator from a reliably red state filibustered the extension of the Patriot Act, opposed the National Defense Authorization Act, opposed SOPA and its variations, and publicly defended innocent citizens from sexual harassment at the airport, most liberty activists would doubtlessly be pleased with such an independent record. As Ron Paul's son there may be expectations among some for Rand Paul in his second year in the senate to be on the same footing as the mature Ron Paul.

But Rand Paul is not in the senate to be the crown prince of the Ron Paul movement. He's a Republican senator from Kentucky and by the standards of what is expected from a truly principled and independent Republican senator he's satisfied more than he's disappointed.

By officially signing on with the Romney candidacy, Rand Paul has something he wouldn't have if he cantankerously opposed Romney as a RINO, socialist, and Obama-lite: political cover.

The real test will come when a President Romney wants to aerial bomb Syria or Iran without a declaration of war. A Senator Paul who stood with his party for the election may not only be in a position to oppose the action, but actually influence people on his own side to do the same.