The president of the United States was both a racist and a very difficult man to get along with.

He routinely called blacks inferior. He bluntly stated that no matter how much progress they made, they must remain so. He openly called critics disloyal, even treasonous. He liberally threw insults like candy during public speeches. He rudely ignored answers he didn’t like. He regularly put other people into positions they didn’t want to be in, then blamed them when things went sour. His own bodyguard later called him “destined to conflict,” a man who “found it impossible to conciliate or temporize.”

But the nation’s politicians simply had to interact with Andrew Johnson, for he had become the legitimate, constitutionally ordained chief executive upon Abraham Lincoln’s death by assassination.

Their path for managing this choleric man reveals that a president need not be kicked out of office to be removed from holding a firm grip on the reins of power. It also shows that people around the president, from Congress to the Cabinet, have many more tools at their disposal than, say, writing an anonymous New York Times op-ed to stop a leader they consider reckless or dangerous.

This is true even thoughJohnson’s vice presidency remains historically unique. For his 1864 reelection bid, Lincoln had dumped his first-term vice president, Hannibal Hamlin. To appeal to non-Republicans and show he wasn’t just a Northern leader in the middle of the Civil War, the president instead ran on a new “National Union” ticket. He picked Johnson, a lifelong Democrat from Tennessee who had been the only senator out of 11 Southern states to remain with the Union in 1861 instead of walking out of the Senate and leaving a vacant seat in protest.

But Johnson turned out to be a poor choice, and the new vice president couldn’t have started his term much worse. Feeling ill, Johnson threw down three glasses of whiskey right before his swearing-in ceremony and inaugural speech. “I need all the strength I can get,” he told Hamlin, who was there to hand off the office Johnson would soon assume. ...