President Donald Trump knew what he was getting with Omarosa Manigault Newman.

When Trump's hires don't work out the way he'd hoped, he has a way of complaining about them as though they were something that just happened to him.

Omarosa was hired when Trump still held the clear view that bitter staff disputes were just part of a healthy workplace.

At campaign rallies, President Trump is fond of reciting the lyrics to "The Snake."

It's a 1968 song by African-American soul singer Al Wilson, about a woman who rescues a frozen snake from the street. She takes the snake home, warms it up, gives it honey — and in return for her trouble, the snake bites and kills her.

Trump, as is his style, has turned the song into a racist parable that warns against trusting entire ethnicities of people — in his telling, Syrian refugees are the snake. This is not what the song is supposed to mean.

But "The Snake" does contain quite good advice if you apply it to individual persons with well-earned reputations for deceit and backstabbing: Do not invite them into your home.

This brings me to Omarosa.

He knew damn well she was a snake before he took her in

On Twitter on Monday, President Trump laid out why Omarosa was an obviously terrible hire for his administration:

When Trump's hires don't work out the way he'd hoped, he has a way of complaining about them as though they were something that just happened to him. Jeff Sessions. Rod Rosenstein. "Sloppy Steve" Bannon. He's outraged, he's surrounded by morons and disloyal losers, none of this is his fault, even though he hired these people.

This is bizarre in general. But it's hilariously bizarre in the case of Omarosa Manigault Newman, whom he called a "lowlife" to reporters on Saturday (and again on Twitter on Monday).

Donald Trump created Omarosa. He made her the supervillain she is today. He is the person who fired her three times on national television.

Sure, she's a lowlife. You can't trust her. I'll stipulate to that. So why the hell did Donald Trump hire her to work in the White House?

Is it because they needed a prominent black voice in the Executive Office of the President and she's his only black friend who isn't Don King?

Actually, that's not it

Trump's own tweets give one reason he hired and retained Omarosa in her job at the White House Office of Public Liaison: She flattered him.

Omarosa's approach of managing up through flattery has worked even for administration officials failing in much more consequential positions: Scott Pruitt retained his job running the Environmental Protection Agency for months, despite alienating virtually everyone in the administration with his scandal tornado, because he stroked Trump's ego.

But I think there are two additional reasons Trump kept Omarosa around, and those reasons provide clues about why he is constantly surrounded by dysfunction.

Trump likes workplace infighting

His instinct is that having his underlings fight one another allows the strong to rise to the top. In the first year of his administration, he fostered an atmosphere of infighting by creating three essentially co-equal West Wing leaders who wished to pursue wildly divergent agendas and also hated one another's guts — Reince Priebus, Steve Bannon, and Jared Kushner.

Eventually, he seems to have realized this was not working out, in part because his staff was spending more time leaking against one another to the press than working. But you have to remember, Omarosa was hired during this period, when Trump still held the clear view that bitter staff disputes were just part of a healthy workplace.

Who better to provoke bitter staff disputes than Omarosa? She is literally the best at it.

Trump likes bad people

The other thing to keep in mind about Trump and Omarosa is that the president's complete lack of moral fiber causes him to admire personality traits that a normal person would view negatively.

Remember, this is a man who brags about being greedy. He praises autocrats who commit extrajudicial killings as "tough." He was close friends with Roy Cohn. Is a person anti-Semitic if he believes in offensive Jewish stereotypes but considers them to be compliments? These are the sorts of questions the Trump presidency forces us to consider.

Trump can look at a conniving, untrustworthy backstabber and see what he likes about himself in that person, and smile — so long as that person is his untrustworthy backstabber.

But the problem with untrustworthy backstabbers is you can't trust them and they will stab you in the back.

The hilarious thing about Omarosa calling Trump a racist and Trump calling Omarosa a lowlife is they are both correct. No two people have ever deserved each other so thoroughly. But we did not deserve this.