McGahn’s service on the Federal Election Commission is a good example. The Commission, created in response to the Nixon campaign’s misdeeds in 1972, is designed to regulate the role of money in America’s elections. Washington’s bureaucratic establishment believes in that. But its Republican establishment does not. And so in 2008, Senator Mitch McConnell—the foremost foe of campaign-finance regulation in Congress—helped put McGahn on the FEC. McGahn was already well-known in GOP circles. He had handled election law for the Bush campaign in 2000 and for a decade served as the lawyer for the National Republican Congressional Committee. During his time at the FEC, one former Commission staffer told Mother Jones, McGahn “seemed mostly interested in grinding its work to a halt.”

From there he went to work at Jones Day, a prestigious law firm long known for its conservative leanings. McGahn’s wife served for many years as staff director of the House Financial Services Committee. Which helps explain why, when McGahn went to work for the Trump campaign, a Washington Post profile called him its “unofficial liaison to the Washington establishment.”

This makes McGahn more vulnerable than many in Trumpland to what that establishment thinks. When Steve Bannon left the White House, he went back to excoriating the Republican establishment at Breitbart. When Jared Kushner leaves, he’ll likely go back to New York real estate. When John Kelly leaves, he’ll presumably have as little do with civilians as possible. But McGahn will probably return to that most Beltway of legal specialties, campaign-finance law, in the Washington office of a major firm. Which means his reputation in Washington—albeit conservative Washington—matters. Even McGahn’s decision to work for Trump, reported the Above the Law blog in 2016, sparked a near-rebellion amongst his colleagues at Jones Day. In the Post profile, a Republican operative wondered why McGahn would give “credibility to Trump in such a way that could damage his reputation for the long term?”

Imagine trying to return to Jones Day—or some equivalent firm—after firing Robert Mueller. In the words of Norm Eisen, President Obama’s former ethics czar, who has tussled with McGahn for many years, “He didn’t want that personal baggage. What’s he going to do for a living, go live in a frat house with Steve Bannon and Dr. Price and Sean Spicer and people that can’t get a job?”

McGahn may have genuinely believed firing Mueller was wrong. But people don’t always do the right thing because a small, still voice tells them to. Sometimes it’s the loud, collective voice of their community threatening them with excommunication.

It’s worth remembering that Elliot Richardson and William Ruckelshaus, who both resigned rather than obey Nixon’s order to fire Watergate Special Prosecutor Archibald Cox, were both deeply ensconced in the Washington establishments of their day. Richardson had already served as secretary of Health, Education, and Welfare and under secretary of Defense. Ruckelshaus had been the first head of the Environmental Protection Agency. Both men’s careers in government preceded the Nixon administration. By contrast, the third in command in Nixon’s Justice Department, Robert Bork, was more of an outsider. He had spent his career outside Washington, in academia, and reportedly fired Cox, in significant measure, because of his deep belief in the constitutionality of executive power.

It’s become commonplace to note that many establishment Republican politicians privately consider Trump unfit to be president but won’t challenge him publicly because he enjoys the support of their constituents. For McGahn, the calculation is different: The members of the Washington Republican establishment are his constituents. And they’ll be around long after Donald Trump is gone.

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