Jonah Goldberg devotes his latest column at National Review Online to detailing the problems plaguing the Republican Party.

Ironically, the institution in which conservatives had their greatest success is the one most besieged by conservatives today: the Republican party. To listen to many grassroots conservatives, the GOP establishment is a cabal of weak-kneed sellouts who regularly light votive candles to a poster of liberal Republican icon Nelson Rockefeller.

This is not only not true, it’s a destructive myth. The Rockefeller Republicans were purged from the GOP decades ago. Their high-water mark was in 1960, when the Goldwater insurgency was temporarily crushed. Richard Nixon agreed to run on a platform all but dictated by Rockefeller and to tap Rockefeller’s minion Henry Cabot Lodge as his running mate. When the forebears of today’s tea partiers threatened to stay home or bolt the party in 1960, Senator Barry Goldwater proclaimed, “Let’s grow up, conservatives!”

It’s still good advice. It’s not that the GOP isn’t conservative enough, it’s that it isn’t tactically smart or persuasive enough to move the rest of the nation in a more conservative direction. Moreover, thanks in part to the myth that all that stands between conservatives and total victory is a philosophically pure GOP, party leaders suffer from a debilitating lack of trust — some of it well earned — from the rank and file.

But politics is about persuasion, and a party consumed by the need to prove its purity to its base is going to have a very hard time proving anything else to the rest of the country.