In his brief spell in the Democratic primaries, former New York mayor Mike Bloomberg ran a series of ads and put up billboards mocking President Trump. They taunted Trump for his inflating his wealth, acting disrespectfully during the national anthem, habitually calling people losers and for everything from cheating at golf to ordering cruddy steaks. Some were silly and a little weird.

On Twitter, Bloomberg routinely would insult Trump in colorful terms:

The efforts were not designed to actually persuade anyone but rather to get under Trump’s skin and present Bloomberg as the guy who could beat Trump at his own game. Bloomberg is out of the race but has said he fully intends to use his fortune to help defeat Trump.

Among others, I have suggested that mass voter registration, litigation against voter suppression laws and sophisticated digital operations should be at the top of Bloomberg’s spending list. However, when it comes to ads, the point should not be to taunt Trump but to mobilize voters and remind those who voted for him in 2016 why they cannot do so again.

There is one message that former vice president Joe Biden may be reluctant to use but that Bloomberg can hammer home: Trump is mentally unfit to hold office — any office, but especially the presidency.

Trump’s statements about the coronavirus, filled with self-congratulations, inanities, falsehoods and non sequiturs, remind us that he is unable to cope with reality; his sole aim is to elevate himself (although his antics make him look ridiculous). He wants a cruise ship to stay offshore so the number of reported cases in the United States will remain artificially low? That’s just nuts, and worse, it is dangerous.

Trump seems to believe that he “knows more about” everything (energy, medicine, diplomacy, nuclear weapons, intelligence, law enforcement, trade, etc.) than anyone, and yet his gaping ignorance and refusal to learn the basic facts imperil the country and the economy. Bloomberg should point this out over and over again.

Trump thinks North Korean dictator Kim Jong Un loves him, so Trump gives up leverage that might force North Korea to denuclearize. Trump trusts the word of Russian President Vladimir Putin over the U.S. intelligence community’s, so Trump refuses to secure America’s elections and tries to extort Ukraine, a U.S. ally. Trump is obsessed with Barack Obama, so he tries to wreck whatever bears his predecessor’s name or is associated with Obama’s legacy, despite his own failure to devise a better alternative (e.g., the Iran deal, Obamacare).

It is not simply that Trump is an ignorant narcissist; rather, the concern is that his ignorant narcissism poses a risk to the country — one that brings us to the brink of war with Iran, emboldens Russia and leaves the United States vulnerable to a pandemic, which in turn may bring on a recession.

Perhaps some voters who cast their ballots for Trump in 2016 did not realize how bad he would be once in office, or they had bet on the Republicans restraining him. Maybe they deeply loathed Hillary Clinton. Now there is no excuse to keep him in power. And Bloomberg’s bottomless wallet should pay for ads to blanket the airwaves reminding them just how dangerous he is.

Moreover, Bloomberg should start now. (Recall how the Obama campaign saturated swing states with anti-Mitt Romney ads in the summer of 2012 before Romney had the money to go on the air.) It is time to fix in voters’ minds that Trump is not only morally reprehensible but also so unfit as to pose a threat to their safety and security.

Use the Post Opinions Simulator to pick a state and see what might happen in upcoming primaries and caucuses.

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