It's too soon to say when Donald Trump's presidency will end, but it's not too soon to say how it will end. It will end in disgrace. And when it does, Trump's defenders will turn on him.

Some already have. On Sunday, Anthony Scaramucci, Trump's former communications director, said that Republicans should "replace the top of the ticket in 2020."

Former White House aide and Apprentice contestant Omarosa Manigault never had a bad word to say about Trump when she worked for him. Trump said he hired her "because she said GREAT things about me." But after she left the White House, she said Trump was "mentally impaired" and accused him of saying the N-word.

Michael Cohen, Trump's former personal attorney, said he was "mesmerized" by Trump when he worked for him. It wasn't until after Cohen quit working for Trump and was sentenced to prison — as a result, in part, of lying for Trump — that he ceased to be mesmerized and instead became disgusted. In congressional testimony, he called Trump a "racist," a "cheat," and a "conman."

Trump's sycophants are as loyal as he is — which is to say, not at all. In The Art of the Deal, Trump counted Roy Cohn as a friend, calling him "a truly loyal guy." After Cohn contracted AIDS, Trump "dropped him like a hot potato," according to Susan Bell, Cohn's longtime secretary. That's the kind of friend Trump is — the kind you don't want.

The people who are loyal to Trump are loyal not because they like him as a person but because they have something to gain from him. In an interview with The New York Times, Sen. Lindsey Graham (R-S.C.) admitted that he embraced Trump "to try to be relevant." So far, his plan has worked superbly — Graham has a recurring slot on Hannity. Once Trump is gone, however, Graham will no longer need the man he once dismissed as "the world's biggest jackass." He will find someone else to latch onto, and he will forget about Trump just as he forgot about John McCain.

Trump's cult of personality is a cult of power-worshippers. "It is the place and power we bow to, not the man," William Hazlitt wrote in his 1823 essay "On the Spirit of Monarchy." When Trump is deprived of his place and power, people will stop bowing to him.

Trump's post-presidency will be sadder and more pathetic than his presidency. His presidential library will be neither presidential nor a library. His memoir, if someone writes one for him, will be dreadful — ghostwritten, poorly written, replete with falsehoods and errors, and bereft of insights and useful information. His presidential papers will contain such statements as "Horseface"; "trade wars are good, and easy to win"; "a very stable genius"; and "your favorite President, me!" No mainstream public figure will want to be associated with his legacy.

In February, 157 scholars ranked Trump as the third-worst president in U.S. history. And it's not just the eggheads who disapprove of him. According to Gallup, 54 percent of Americans disapprove of his presidency. Trump has averaged the lowest approval rating of any president in history. Unlike his predecessors, Trump doesn't need a war or a recession to be unpopular — he just needs himself. And unlike his predecessors, Trump won't improve his public standing as a private citizen.

After resigning in disgrace, Richard Nixon partially rehabilitated himself. He wrote a 1,120-page memoir and a succession of books about foreign policy. He counseled presidents and appeared on serious news programs to opine on world events. Time columnist Hugh Sidey, who had chided Nixon during Watergate, called him a "strategic genius." President Clinton gave Nixon a fawning eulogy.

Jimmy Carter is widely regarded as having been a better ex-president than a president. His approval rating rose from 31 percent in 1980 to 64 percent in 2009, thanks largely to his humanitarian work. According to The Washington Post, he "helped renovate 4,300 homes in 14 countries for Habitat for Humanity." Trump, on the other hand, reportedly appropriated money meant for a children's cancer charity.

In the early republic, ex-presidents returned to private life. That changed with John Quincy Adams, who broke with tradition and entered the U.S. House of Representatives. Over time, ex-presidents began to monetize their experience. In 1885, Ulysses S. Grant sold his memoirs for $450,000. Nixon received a $2.5 million advance for his. Clinton made millions of dollars giving speeches.

Trump will try to profit, too, of course. He already runs an online store on his personal website, where you can purchase a MAGA bathing suit for $55 and a "WITCH HUNT" coffee mug for $30. But the market for Trump regalia will shrink when he's out of office. Of his poorly educated supporters, how many will spend $30 on a memoir they won't read? Who will pay to hear Trump blabber about nothing when he already does that for free? Won't people tire of him?

They already are. On his wife's birthday last year, Trump called Fox & Friends and rambled for so long that the hosts didn't know how to get rid of him. After waiting patiently for 30 minutes, Brian Kilmeade politely informed the unhinged man on the other line that he probably had "a billion things" to do that day, his being president and all.

After Trump leaves office and has fewer things to do, people will have fewer reasons to listen to him. Ex-President Trump will call Fox & Friends every morning, but they will ignore him. Instead of ranting on air, he will leave voicemails for Steve Doocy's assistant's intern.