Former National Security Adviser John Bolton is the man of the hour. His forthcoming book, as summarized by The New York Times and other media outlets, appears to undermine the "no quid pro quo" defense of President Trump. He may have pried loose the Republican votes necessary to hear from additional witnesses and keep the Senate trial going. We may even get testimony from Bolton himself.

Bolton is now getting fulsome praise in quarters where he was previously dismissed as a mustachioed menace. The Resistance recognizes that he may give them their best shot to take Trump down. But is Bolton, a creature of the conservative movement who relies on the Republican Party for influence, really ready to go the route of John Dean, the fired White House counsel whose Senate testimony in 1973 led to President Richard Nixon's resignation?

Under Trump, we have seen a split among neoconservatives and other inveterate Republican hawks. Some have become such Never Trump mainstays that they functionally align with the left in opposition to the president, cultivating new audiences for themselves. Former Weekly Standard editor Bill Kristol, attorney George Conway (husband of Kellyanne), and Washington Post columnists Jennifer Rubin and Max Boot fit in this category. Others, like Sens. Tom Cotton and Lindsey Graham, have tried to win Trump's favor.

Bolton's role in the latter camp briefly won him a spot as national security adviser to the president. As his foreign-policy differences with Trump mounted, he was eventually cashiered. He no doubt feels burned by Trump and his erstwhile colleagues who outmaneuvered him in Washington's bureaucratic games. This would be an unparalleled opportunity for revenge and perhaps a chance to install, via Vice President Mike Pence, a president more to his liking on these issues.

Except Bolton isn't exactly like the Kristols and the Boots. Taking down a Republican president could permanently damage his brand and influence with the people he needs to accomplish his policy objectives. Is Bolton prepared to do that?

Much is made of the fact that Bolton is not, strictly speaking, a neoconservative. In foreign policy terms, this matters little: He may be more skeptical than they of democracy promotion and some of the more idealistic arguments employed on behalf of the Iraq invasion, but he generally supports all the same wars. His threshold for the use of military force is lower than that which prevailed under Ronald Reagan or George H.W. Bush.

Yet in domestic politics, it may matter more. Bolton isn't a liberal mugged by reality. His conservatism dates back to Barry Goldwater's 1964 presidential campaign. He does not find rank-and-file Republicans uncouth. Trump voters are a natural audience for his speeches, television appearances, and books — at least until now.

While the fear that Trump would be insufficiently hawkish is a quiet motivation of many Never Trumpers on the right, Kristol, Rubin, and Boot have to some extent de-emphasized their foreign policy views as they have pursued a new following among the MSNBC set. Rubin in particular has criticized Iran moves by Trump she almost certainly would have praised if done by another Republican.

Bolton isn't going to be able to do that, at least not so easily. His preferred foreign policy matters to him and it is only going to come to fruition under Republican presidents. He has appeared at events like the National Conservatism Summit in order to steer the new nationalist, populist right in a more hawkish and interventionist direction. He does not want to cede the field to Tucker Carlson.

How much does any of this matter? If Bolton testifies, what matters most is what he saw and whether that is helpful or harmful to the president. Even if they don't make Trump's removal more likely, his revelations could become a damaging campaign issue. They could also secure majority support for an article of impeachment even if the votes to convict fall well below the required two-thirds.

But if Bolton isn't ready to jump from the Trump Train to the Resistance, if he continues to have policies he needs Republicans to champion and he remains more Fox News than MSNBC, it could color his much anticipated testimony at the margins. Maybe he won't go the full John Dean. Or maybe there will be surprises that partisans of both stripes can't predict.

If John Bolton looks like an unlikely hero for the Democrats, that's for one very simple reason: He is.

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