Instead, by arguing that collusion with a foreign government is fine, Hannity and Gingrich have given themselves license to defend almost anything that now comes out. McClatchy reported on Wednesday that congressional and justice department investigators are looking into whether the Trump campaign helped direct Russia’s fake news attacks against Hillary Clinton. Hannity and Gingrich now have their answer: Collusion is fine. The fact that Rob Goldstone, in his email to Donald Jr., said the meeting with Veselnitskaya was “part of Russia and its government’s support for Mr. Trump” and that he suggested “I can also send this info to your father via Rhona [his secretary]” suggests that President Trump may well have known his campaign was colluding with Russia. But Trump’s defenders now have a justification for that too.

Trump and his defenders have executed this maneuver before. Last fall, when the release of the Access Hollywood tape, combined with numerous allegations of sexual harassment, imperiled Trump’s campaign, his defenders began focusing on Bill Clinton’s sexual indiscretions. The Trump campaign even invited three Clinton accusers to the October 9 presidential debate. The implication was clear: Lots of powerful men sexually harass women. It didn’t disqualify Clinton; it shouldn’t disqualify Trump. No big deal.

For conservatives, this week’s revelations mark a fork in the road. In its editorial on the matter, National Review took a radically different tack than Hannity and Gingrich. The magazine said that if “nothing else came of” the meeting with Veselnitskaya, it might not be that big a deal. But it didn’t say collusion was fine. To the contrary, it warned that if “the Trump Jr. meeting is only the beginning of damaging revelations about some sort of relationship between a Russian government determined to try to tip the scales in an American presidential election and the Trump campaign” that would constitute a grave offense.

In contrast to Hannity and Gingrich, who this week set themselves up to defend Trump no matter what, National Review has now laid the foundations for turning on him.

It comes down a simple question: Can Trump do anything wrong? By laying out what it would consider wrongdoing, National Review has answered yes. It has set out a standard for Robert Mueller, the special counsel investigating collusion between Russia and the Trump campaign, to meet. By shifting their argument to “everyone does it,” Hannity and Gingrich have essentially answered no, nothing Trump could have done would qualify as wrongdoing. It is, after all, always possible to find examples of other people doing bad things. Remember what Trump said in December 2015 when Joe Scarborough pushed him about Putin’s murder of journalists: “I think our country does plenty of killing also.”

It’s now easier to predict which conservatives will defend Trump to the end and which conservatives will not. The argument between them will help determine whether his presidency survives.

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