President Trump said the media in many cases "doesn't want to report on" terrorism, speaking to senior U.S. military commanders and coalition representatives on Feb. 6 at MacDill Air Force Base in Florida. (The Washington Post)

President Trump has said lots of negative things about the media since he began running for the White House in June 2015. He's called reporters “the most dishonest people.” He's called out individual reporters for alleged bias. He's insisted that the media as a whole is failing. Heck, he even once called me “one of the dumber and least respected of the political pundits.”

But, to my mind, all of that name-calling pales in comparison to Trump's insinuation Monday that the media is purposely covering up terrorist attacks. Here's the key bit of what Trump said at U.S. Central Command in Florida:

You’ve seen what happened in Paris, and Nice. All over Europe, it’s happening. It’s gotten to a point where it’s not even being reported. And in many cases the very, very dishonest press doesn’t want to report it. They have their reasons, and you understand that.

Trump said, “They have their reasons, and you understand that.”

He didn't offer any more explanation. Just that.

White House press secretary Sean Spicer, pressed on Trump's comment on the flight from Florida back to Washington, stood up for his boss.

Where to start? How about:

1. The media did cover every single one of the terrorist attacks Trump mentions. Extensively.

2. It's deeply irresponsible to suggest — with no evidence — that the news media is ignoring news events because they don't fit some sort of hidden journalistic agenda.

That second point is why what Trump is saying is so, so dangerous. He's implying that the media is allowing its own collective biases to get in the way of his efforts to keep the country safe from the threat of terrorism. That the media is, at best, downplaying these attacks because of their own ideological biases and, at, worst, siding with the terrorists. That's staggering stuff — even for Trump.

As Philip Bump notes, it's not the first time Trump has made an insinuation like this one. In June 2016, in the wake of the Orlando nightclub massacre, Trump said this: “People cannot believe that President Obama is acting the way he acts and can’t even mention the words radical Islamic terrorism. There’s something going on.

“They have their reasons … and you understand that.”

“There's something going on.”

Notice the similarities? A suggestion of nefariousness without any evidence to back it up.

The problem is this: For lots and lots of people listening to Trump, his suggestion that the media is complicit in a coverup of terrorist attacks will be taken as fact. They won't seek out context or evidence that, frankly, totally undermines his contention. Because they already believe the media to be bad/biased, they will simply take it as a fact that the media is willfully disrupting the president's efforts to keep the country safe.

The job of a leader isn't to give people what they want — especially if you know (or suspect) it's not entirely accurate. If Trump has evidence that the media has covered up a terrorist attack — or downplayed it in any way — he should come forward with it. Spicer suggested Trump will do just that.

I look forward to that list. Without it, what Trump is doing is leveling a baseless allegation. And baseless allegations from the president of the United States are very dangerous things.