The GOP’s elite anti-birther backlash against Trump is now in full swing, as Trump rises in the polls and everyone tries to figure out whether his candidacy is legitimate or Andy Kaufman-esque political performance art. George Will is warning that Trump could “make a shambles of the Republican debate just by being there,” while Charles Krauthammer proclaimed that Trump is the GOP’s Al Sharpton.

There’s only one problem with this analogy: When Sharpton ran for president, he never did anywhere near as well as Trump in the polls. This may simply be a function of the GOP not liking their choices — only Mitt Romney broke double digits in the latest Post poll — but Trump’s strong showing obviously has some Republicans worried that he could have a real impact on the race.

Krauthammer and Will are only the latest conservative commentators to diss Trump. Republican Party leaders and conservative commentators like Karl Rove, Ann Coulter and Peter Wehner have already been sounding the alarm about Trump. Yet this is about more than Trump: At bottom, the effort to discredit him reflects the GOP establishment ongoing effort to wean the Republican Party off of its birtherism problem. Establishment presidential candidates like Mitt Romney and Tim Pawlenty dismissed the false rumors about the president’s birth as a non-issue. And the GOP’s birther problem isn’t even confining itself to the presidential nomination contest: Yesterday, Arizona Governor Jan Brewer had to veto a bill that would have required presidential candidates to submit a “long form birth certificate” in order to make it on the ballot.

Here’s the thing: Trump’s candidacy is largely a problem of the GOP’s own making. It’s a symptom of circumstances Republicans have spent the last two years tacitly cultivating as an asset. Republican leaders have at best refused to tamp down the most outlandish right-wing conspiracy-mongering about the president and at worst have actively enabled it. The result: A substantial portion of their base believes a complete myth about the president’s birth certificate, and Republicans are stuck with a candidate shameless enough to exploit the issue without resorting to the usual euphemisms more respectable Republicans tend to employ when hinting at the president’s supposed cultural otherness.

I don’t know how you solve a problem like Donald Trump, but I know it’s a problem the Republican Party brought on itself.