I’m generally unmoved by the kind of polemical thunder Erick Erickson unleashed on Virginia Gov. Bob McDonnell:

Bob McDonnell is a perfect example of the worst kind of Republican. He has no principles that he won’t sell out if he thinks the situation demands it. He is interested in the praise of liberal editorial pages for his balanced leadership, which is really just selling out the people who got him elected. His policy legacy will now be trading higher taxes for a massive entitlement expansion. How pathetic.

That’s how Erickson ended his broadside.

He began it by calling McDonnell a “liar.”

And he’s got a point.

McDonnell’s problems with conservatives (including the Republican lieutenant governor who hopes to succeed him) are twofold. He is on the brink of signing a massive transportation bill that could, when fully implemented, raise taxes on Virginians by $6.1 billion over the next five years, according to Grover Norquist’s Americans for Tax Reform. And he issued a statement in support of a bicameral commission on reforming Medicaid, which Erickson predicts “will be nothing but a speed bump towards expanding the program.” (Jennifer Rubin, with characteristic credulity, said “the state can be assured Medicaid isn’t expanding anytime soon.” I’d say the smart money is with Erickson in this case.)

Against the backdrop of the fractious fiscal situation across the Potomac River, McDonnell’s transportation deal might appear to be the work of a sane, well-functioning government. Yet the fact is that McDonnell didn’t merely promise not to raise taxes in a general George H.W. Bush sense—although he did that, too. McDonnell explicitly promised not to sign a transportation bill that had new revenue.

What we’ve got here is a granular, issue-specific about-face.

I would add, as an aside, that state politicians with national aspirations should avoid taking Norquist-like pledges that any politician of consequence in this fiscal environment will need to wriggle out of. But in McDonnell’s case, that horse left the barn four years ago.

Conservatives like Erickson are right to be pissed.

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