Donald Trump isn’t the first president to be undermined by a senior official who claims to be saving the Republic from the chief executive he formally serves. The role of secret internal resister within the White House was first pioneered by Attorney General Edwin Stanton, perhaps the most relentless schemer in American political history. Stanton’s strange career is also an object lesson on the folly of trusting those claiming to play a role that, after all, requires a talent for deception.

Stanton joined the cabinet of lame-duck President James Buchanan on Dec. 20, 1860, the same day South Carolina seceded from the Union. Buchanan, a Democrat who was both loyal to the Union and personally friendly with many of those bent on destroying it, didn’t know what to do about the crisis in which he found himself. Mostly he blamed the Republicans and pitied himself, while many of his most trusted advisers did everything they could to weaken the government before resigning to serve the Confederacy.

Before joining the cabinet, Stanton’s most noteworthy achievement had been successfully defending Buchanan’s friend Rep. Daniel Sickles of New York, on murder charges. Sickles had fatally shot his wife’s lover, who also happened to be U.S. attorney for the District of Columbia, in the middle of the day, steps from the White House. Stanton argued that Sickles was morally and legally justified in killing his wife’s seducer because—well, wouldn’t you? That was enough for the jury. Sickles was carried out of the courthouse like a hero, and Stanton earned Buchanan’s gratitude.

Immediately after taking office as attorney general, Stanton offered himself to several prominent Republicans as a spy within the administration. He mortified them with tales of imbecility and treason. One of them, Sen. Henry Wilson of Massachusetts, recalled that it was “strikingly providential” that Buchanan had brought “that strong, rugged, downright, patriotic man” into his cabinet at such a fateful hour. In secret midnight meetings, Stanton told Wilson of his heroic efforts to save the republic from its treacherous chief executive. 

“The President—poor, weak old man—trembled and grew pale,” Wilson quoted Stanton as saying. But for himself, Stanton claimed, the nation would have been dismembered by traitors before Lincoln and the Republicans took power. It’s a dramatic story, but alas, Stanton was lying—to the Republicans, to Buchanan, to everyone. ...