Stephen Colbert probed CNN’s reporting of former White House insiders telling them that since midterm elections and trip to Paris, President Donald Trump is “pissed at damn near everyone.”

Wow! Being president has really worn him down!” Colbert rued.

“Remember Inauguration Day, when he as so lighthearted and filled with joy?” he added, as Late Show began clip of Trump’s “American Carnage” inaugural address.

Another former staffer reported Trump’s behavior is now at “a level of insanity I’ve never seen before,” Colbert read, telling his audience, “Keep in mind, this White House has seen Kanye.”

Current and former Trump White House staffers are debating what has triggered outbursts with theories ranging from his fears over son Don Jr.’s legal exposure to the prospect of House Dems unleashing investigations in January.

Colbert added some of his own:

-Stock market going up and down

-Existence of stairs

-Possible McRib shortage

News cycle this week has been abuzz with reports Trump is about to fire a bunch of people, including Chief of Staff John Kelly.

Kelly, however, has decided to “hang in there and get humiliated day after day,” Colbert reported, adding, “I think that’s actually a White House motivational poster.”

Trump’s reasoning: The more the press writes that John Kelly is gone, the more Trump is emboldened to keep him, just to prove them wrong.

“There’s your ‘stable genius’ at work right there!” Colbert snarked, throwing back to Trump’s description of self after Michael Wolff claimed some Trump’s aides doubted his mental fitness for office.