Can you tell if President Trump is speaking from a teleprompter or off the cuff? Here’s a look at his sporadic speaking styles. (Elyse Samuels/The Washington Post)

Can you tell if President Trump is speaking from a teleprompter or off the cuff? Here’s a look at his sporadic speaking styles. (Elyse Samuels/The Washington Post)

And so, on one day, we had an unhinged and divisive rant by President Trump in Phoenix. Then, the next day in Reno, Nev., a call for national unity and reconciliation. Multiple political personality disorder. Rhetorical schizophrenia.

The gap between Trump extemporaneous and Trump scripted is canyon-like. The normal role of a speechwriter is to find, refine and elevate the voice of a leader. The greatest professional victory comes when a president thinks: This is the way I would sound if I had more time to write and more talent with language. In these circumstances, speechwriting is not deception; it is amplification.

But what about speechwriting that is designed to give a leader a different voice? Here moral issues begin to lurk. Is it ethical to make a cynical leader appear principled? A violent leader seem pacific? A cruel leader seem compassionate? This calculation is difficult, because most of us have an incongruous mix of such traits. Or maybe a speechwriter can hope a president will eventually rise to the level of his teleprompter.

My purpose is not to indict the president’s speechwriters. It is to point out that, in Trump’s case, there is no doubt which is his authentic voice, because he leaves no room for doubt. In rambling stemwinders such as the one in Phoenix, he plays rhetorical games with the artificial (for him) constraints of being presidential. “Nobody wants me to talk about your other senator — who’s weak on borders, weak on crime,” he said of (conservative Republican) Jeff Flake. “Now everybody’s happy.” Here the “nobody” clearly included his own concerned advisers. Trump often uses speeches (and Twitter) to cut the strings of their counsel.

Trump deserves a patent on the idea that political authenticity means spontaneity. So it was the real voice that we heard in Phoenix, attacking a man with brain cancer — Republican Sen. John McCain — without any wish for his recovery. The real voice defending a supporter who had been fired by CNN for writing “Sieg Heil” on Twitter. The real voice making fun of a TV anchor’s height. The real voice again widening racial divisions by defending Confederate monuments as “our history and our heritage.” (Instead of the royal “we,” the white “we.”) It was the real voice expressing greater passion in criticizing journalists than white supremacists.

President Trump speaks in Phoenix. (Alex Brandon/Associated Press)

Trump dares us to take him at face value. His self-revelation comes unbidden, even involuntarily. And his transparency reveals a disordered personality.

Why does this matter? For one thing, his Phoenix remarks indicate a loose connection to reality. His response to the violence in Charlottesville was, in his view, “perfect.” The North Koreans, he claimed, are learning to “respect” America (for which there is no evidence). “I don’t believe that any president has accomplished as much as this president in the first six or seven months,” Trump claimed of himself. “I really do not believe it.”

What if Trump really believes what he claims? Then he would be not deceptive, but deluded. A deluded man in charge of North Korean policy. A deluded man who could employ nuclear weapons at a moment’s notice (actually two to three minutes to order a launch). This appears to be the reason that national security professionals such as former director of national intelligence James R. Clapper Jr. and former acting CIA director John McLaughlin have been particularly disturbed of late. Trump is not merely acting unpresidential; he is erratic and grandiose.

This also matters in a domestic context. On the evidence of the Phoenix speech, Trump believes that a government shutdown is preferable to giving up on funding for the southern border wall. This involves a different type of delusion. Poll after poll demonstrates that about 35 percent of Americans support Trump’s wall. You can’t hold national parks and veterans’ payments hostage over an issue like this and expect to win.

Adds one Republican budget expert I spoke with: “It also takes careful management of the levers available to the administration in a shutdown to keep it from becoming a nightmare immediately, and OMB [Office of Management and Budget] is not doing the work to prepare. Incompetence is the death of these guys over and over.”

Senate Majority Leader Mitch McConnell (R-Ky.) and House Speaker Paul D. Ryan (R-Wis.) know a shutdown would not turn out well. But Trump’s version of reality appears to make another Republican legislative and political disaster inevitable. The unified control of House, Senate and presidency means little when the president lives in a reality of his own.

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