Donald Trump has already told us who his new national security adviser will be

Take the ongoing search for his next national security adviser -- his 4th in less than 3 years! -- following the firing of John Bolton last week. Here's Trump from late last week on the job:

"It's a great job. It's great because it's a lot of fun to work with Donald Trump. And it's very easy actually to work with me. You know why it's easy? Because I make all the decisions."

See! He says it right there! Donald Trump's next national security adviser will be none other than Donald Trump himself!

I kid, but not really. Because what Trump said about the national security adviser job echoes past statements he's made about other key openings in his administration.

Back in 2017, Trump was asked by conservative talk show host Laura Ingraham if he had enough State Department employees in place to push through his policies. He responded this way:

"Let me tell you, the one that matters is me. I'm the only one that matters, because when it comes to it, that's what the policy is going to be. You've seen that, you've seen it strongly."

"I make all the decisions." "I'm the only the matters." And, for good measure, throw in the famous/infamous Trump pronouncement that "I know more about ISIS than the generals do." (Axios has a helpful list of all the things Trump says he knows more about than anyone else in the world.)

There's a clear pattern here: Trump views himself as the only indispensable member of his administration, the person who makes all the calls because he knows more about any given subject than the so-called experts and because, well, he's the President and they're not.

Now. All presidents -- Republican and Democrat -- have a healthy ego and an innate trust in their decision-making abilities. It's what allows them to believe that they are qualified to represent a diverse country of more than 300 million people.

But, Trump takes this idea to an absolute extreme. He is so focused on ensuring that the public knows a) he's in charge b) he's very smart and c) he has the best judgment that he is unwilling or unable to allow others to get attention or credit. This is the Donald Trump Show, not the national security adviser show, after all!

There are obvious limitations to that me-me-me approach to governance. The job of president is so big and carries with it so many varied challenges that it is literally impossible for all expertise and decision-making to lie in the hands of one person. Sure, on the biggest issues -- military intervention and the like -- the last and decisive word comes from the president. But, there are a whole lot of smaller decisions that happen 1,000 times a day across government that a president should leave to the true experts in the field.

Because Trump believes himself to be an expert in every field -- and because he is deeply concerned about the image that he is not totally in charge -- he tries to make all sorts of calls and decisions that in past administrations were left to cabinet secretaries and senior staff.

What that approach creates is a yo-yoing effect as a president who lacks expertise in, say, Iran nuclear talks goes from insisting one week that he would be open to meeting with the country's leader with no preconditions to tweeting this on Sunday night: "The Fake News is saying that I am willing to meet with Iran, 'No Conditions.' That is an incorrect statement (as usual!)."

Who Trump eventually names as his national security adviser, then, is immaterial. Trump is the national security adviser. And the secretary of state. And the secretary of defense. And if the people ostensibly in those jobs don't like it -- or try to carve out their own power center within the organization -- they won't have the job for long.

Because, after all, he "makes all the decisions."