(CNN) To understand how Donald Trump thinks and operates as president, you need to understand where he comes from. Trump was formed largely, as a product of two major forces: New York media's insatiable appetite for news and gossip and reality TV.

He came of age in the " Bright Lights, Big City " Manhattan. He was covered as a sort of bad boy of New York City gossip -- his every move consumed by the tabloids. He spent his last decade-plus creating "reality" TV in which he and his producers made extremely watchable TV out of human emotions and foibles.

In short: Donald Trump has spent his whole life manipulating his image through the news and TV. Which brings me to Trump's Wednesday morning tweet that he had selected Christopher Wray to succeed deposed director James Comey at the FBI

It is impossible to see the move as anything other than Trump throwing some chum to the news gods -- and some news that tells a much more positive story for this White House than the testimony expected later today from deputy Attorney General Rod Rosenstein and, especially, from Comey on Thursday.

Trump knows that the next 48 hours are going to be very, very rough for him. No matter how confident he acts publicly about the Comey testimony -- "I wish him luck," Trump said on Tuesday when asked about it -- Trump has to be worried about the prospect of the former FBI director directly contradicting the idea that he reassured the president that Trump was not under investigation.

Trump has backed himself into a major corner with his full-scale denials about the reporting coming out of his conversations with Comey. And, when backed into a corner, Trump is doing what he has spent a lifetime doing: Try like hell to change the subject and focus of the media lens.

It's transparent -- and far from foolproof. But, it is working, at least somewhat.

Already former Department of Justice official (and Democrat) Matthew Miller is out with a tweet praising the pick . "Wray probably the best choice from the WH short list. His record in the Bush DOJ deserves scrutiny, but he's a serious, respectable pick," tweeted Miller. Added Carrie Johnson , who covers the Justice Department for NPR: "Christopher Wray, Trump's pick to lead FBI, was respected by career DOJ prosecutors when he led criminal division. Solid, not flashy, guy."

And, as of 9 a.m., the CNN website was leading with the Wray pick. Ditto NBC and Fox News. It was the off-lead story on the websites of the Washington Post and the New York Times websites. In all cases the Wray news competed with stories previewing the Comey testimony and the news that Attorney Gneral Jeff Sessions had threatened to resign

That won't extend all day. Depending on what Rosenstein and Director of National Intelligence Dan Coats tell the Senate Intelligence committee today , they could become the big story. And, by later this afternoon, the coming Comey testimony will be the story that sucks up all of the news oxygen.

But nominating Wray gives Trump a temporary respite from the relentless -- and negative -- coverage about Russia, Comey and the rest. It also gives him something to talk about in which he doesn't appear angry and defensive. (By the way, that's the same motivation behind Trump's speech bashing Obamacare in Cincinnati this afternoon.)

Manipulating media coverage -- and perceptions about him more generally -- is in Trump's DNA. It's who he is. It's what he does. Hence, the Wray nomination on the verge of what almost certainly will be one of the roughest two-day patches of his presidency to date.