Joe Scarborough, the host of MSNBC's "Morning Joe," has now officially gone off the deep end.

In a bizarre rant on Thursday morning, Scarborough said President Trump is mentally unfit for office and claimed that "people close to him during the campaign" have told him that Trump suffers from dementia. Scarborough went even further, saying the Constitution's 25th Amendment allows for Trump's removal from office — in fact, demands it.

"If this is not what the 25th Amendment was drafted for — I would like the Cabinet members, serving America, not the president, serving America ... you don't represent him," Scarborough sputtered incoherently.

Talking directly to Trump — who no doubt was not watching the hard left show — Scarborough said: "You represent 325 million people whose lives are literally in your hands, and we are facing a showdown with a nuclear power and you have somebody inside the White House that the New York Daily News says is mentally unfit; that people close to him say is mentally unfit; that people close to him during the campaign told me had early stages of dementia."

“When are we supposed to say this?” Scarborough asked. “After the first nuclear missile goes? Is that when it's proper to bring this up in polite society?"

In the end, Scarborough said “America will survive this," but — "at this particular moment ... we are headed toward a nuclear showdown ... We are closer to a war on the Korean Peninsula than most Americans know."

The 25th Amendment allows for the president to be removed from office when “he is unable to discharge the powers and duties of his office.” It states: "Whenever the Vice President and a majority of either the principal officers of the executive departments [the Cabinet] or of such other body as Congress may by law provide ..." the president can be removed.

Scarborough's rant followed President Trump's tweet on Wednesday aimed at NBC executives and "Morning Joe" host Joe Scarborough:

Trump tweeted: "So now that Matt Lauer is gone when will the Fake News practitioners at NBC be terminating the contract of Phil Griffin? And will they terminate low ratings Joe Scarborough based on the 'unsolved mystery' that took place in Florida years ago? Investigate!"

In 2001, two months after Scarborough announced his retirement from Congress, a 28-year-old intern was found dead in a Florida district office, reportedly of natural causes.

Opening Thursday's show, co-host Mika Brzezinski read from a New York Daily News piece that said, "Only those completely under his spell can deny what growing numbers of Americans have long suspected: The President of the United States is profoundly unstable. He is mad. He is by any honest layman's definition mentally unwell."

"And this comes in the midst of a nuclear showdown with North Korea," Scarborough said. “So I'm just kind of wondering — what's the Cabinet waiting for? What are Republicans in the House and Senate — because it's never going to get more deadly serious than it is now."

Defending her fiance, Brzezinski read a statement she said she wrote:

Today the president crossed another deep and disturbing line with his attacks on Joe. The chief law enforcement officer of the United States of America advanced a false conspiracy theory to intimidate the press and cause a chilling effect on the First Amendment.

Joe and I are not intimidated. And his bizarre behavior contravenes both the Constitution and basic moral judgment.

This is the new line of attack: Trump has gone mad. Apparently the Left has bailed on the whole "Russia did it" meme and has decided this is the most fruitful line of attack.

Good luck with all that.