Then-Republican presidential candidate Donald Trump with Joe Arpaio, then the sheriff of Maricopa County, Ariz., in 2016. (Mary Altaffer/Associated Press)

Coming a week after President Trump’s disastrous comments about Charlottesville and a day after a speech about sending more young men and women into combat, Trump’s choice to go to Arizona for a campaign-style rally is bizarre, even for him. It is now when he should be reassuring the country that he’s mentally and emotionally fit to lead. Americans are entitled to question the judgment of a president who just days ago was repeating (approvingly!) a known hoax about Gen. John J. Pershing committing war crimes against Muslim rebels. A demonstration of maturity and sobriety would seem to be in order. Trump is not capable of such displays, at least not for more than a day in a row.

So given all that, how will it help Trump, his party or the country to stick him in front of an audience of his true-believing fans in a setting where he delivered a campaign speech urging mass deportation? We know in this kind of venue he cannot possibly withstand the urge to demagogue. No script or teleprompter is going to restrain him. Moreover, we know his presence will bring out a massive (we hope, peaceful) protest. We’ll see the signs and hear the angry voices, and once again Americans will be baited into divisive arguments. Trump apologists will demonize protesters, while anti-Trump forces will return the favor. This event promises to be the antithesis of a presidential appearance. Instead, be prepared for a glaring contrast to Monday’s night plea for the country to rally round him.

Former Maricopa County, Ariz., sheriff Joe Arpaio ignored a judge's order to stop detaining people because he merely suspected them of being undocumented immigrants. (Thomas Johnson/The Washington Post)

Trump’s presence is so divisive that not even the GOP governor is showing up. According to local Arizona press, “Gov. Doug Ducey will greet President Donald Trump on the tarmac after Air Force One touches down Tuesday afternoon for his first presidential visit to the Grand Canyon state. But the Republican governor, who like many in the GOP has diplomatically sidestepped Trump and his more divisive rhetoric, will not attend Trump’s campaign-style rally at the Phoenix Convention Center.” It’s not a complete snub, but it is a way of avoiding associating the governor with Trump’s agenda and rhetoric. It’s a measure of Trump’s toxicity that he cannot go to a red state he won in 2016 without provoking mass protests and chasing away the governor of his own party.

Meanwhile, other state Republicans are nervous he’s going to expand upon his Twitter endorsement of gadfly and one-time Senate race loser Kelli Ward, who is launching a primary challenge to Sen. Jeff Flake (R-Ariz.). The Post reports:

That possibility has unnerved Republicans inside and outside the White House. Some worry about straining the president’s already tenuous relations with congressional Republicans at a time when they face several key challenges this fall: raising the debt ceiling, passing a spending bill and tackling their top policy objective of new tax legislation. Others looking ahead to next year’s midterm elections think Trump may even be putting the Senate GOP majority at risk.

The only thing that could make the whole affair into a full-blown catastrophe would be Trump’s pardon for former sheriff Joe Arpaio, a hero of the anti-immigrant crowd, who was convicted of criminal contempt for defying a court order to cease racial profiling. In pleading with the president to stay away, Phoenix’s mayor writes, “A pardon of Arpaio can be viewed only as a presidential endorsement of the lawlessness and discrimination that terrorized Phoenix’s Latino community. Choosing to announce it in Phoenix — especially in the wake of Charlottesville — would add insult to very serious injury and would reveal that the president’s true intent is to further divide our nation.” It’s an idea so outrageous, only Trump would seriously consider it.

The Phoenix visit and potential pardon demonstrate once again that Trump is incapable of leading and unifying a great, diverse country. His yearning for adulation and incapacity for empathy or graciousness cast him in the perpetual role of instigator, divider and provocateur when he should be healing, uniting and inspiring a country he was elected to lead and which he is committing to continued war. Never has a president been so ill-suited to the moment and the needs of the country.