(CNN) On Saturday night at a rally in Washington, Michigan, President Donald Trump said this of Montana Democratic Sen. Jon Tester: "I know things about the senator I can say, too. If I said them, he would never be elected again."

Let's be clear what happened here: The sitting President of the United States told a crowd that he has information on a sitting US Senator that, if revealed, would guarantee that the senator would lose re-election this fall.

What we know of all of this is far less than what we don't know, so let's deal with that first.

We know that Trump is angry at Tester, the ranking Democrat on the Senate Veterans Affairs Committee, for releasing a memo documenting the various allegations made against Ronny Jackson, the President's nominee to head the VA, by whistleblowers. Those accusations range from Jackson writing himself his own prescriptions to being intoxicated on a foreign trip with then President Barack Obama. Jackson withdrew his name from consideration amid the turmoil but Trump continues to insist that Jackson, who has taken care of the President as the White House physician, is entirely innocent.

"They did that to Admiral Jackson," Trump said on Saturday night. "They are doing it for a lot of people."

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