It's not yet clear who, if anyone, senators will hear witness testimony from in Donald Trump's impeachment trial, but one name keeps coming up for a reason. Former White House National Security Adviser John Bolton has first-hand information about the president's culpability; he's volunteered to testify; and it's obvious he'd present senators with a more complete picture of what transpired in the Ukraine scandal.

All of this, evidently, is causing Trump and his allies quite a bit of anxiety.

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Indeed, they're getting a little weird about it. The president tweeted yesterday, "They didn't want John Bolton and others in the House. They were in too much of a rush. Now they want them all in the Senate. Not supposed to be that way!" It was bizarre: House Democrats desperately wanted to hear from Bolton and asked him to testify. As House Intelligence Committee Chairman Adam Schiff reminded Trump, the president is the one who ordered Bolton to remain silent.

The Washington Post reported that there are related behind-the-scenes efforts underway, driven entirely by Republican fears of possible Bolton testimony.

President Trump's legal defense team and Senate GOP allies are quietly gaming out contingency plans should Democrats win enough votes to force witnesses to testify in the impeachment trial, including an effort to keep former national security adviser John Bolton from the spotlight, according to multiple officials familiar with the discussions. [...] One option being discussed, according to a senior administration official, would be to move Bolton's testimony to a classified setting because of national security concerns, ensuring that it is not public.

There are two key elements to this that are worth keeping in mind as the process moves forward. First, manufacturing pretextual "national security concerns" because Republicans fear a Republican witness telling the truth is a ridiculous abuse.

Second, for all of the incessant rhetoric from the White House and its allies about Trump being completely innocent and assurances that the whole scandal is a hollow hoax, the innocent don't generally scramble to block, stifle, and obscure important witness testimony.

Or put another way, when Team Trump acts like it has something to hide, it's probably because Team Trump has something to hide.

The Wall Street Journal added yesterday that the president "has said he would probably try to block attempts to call John Bolton." Of course, in procedural terms, it's not up to Trump to block or allow various witnesses; it's up to the Senate.

And therein lies the broader point: the only way for the president to get away with this is for Senate Republicans to act as his accomplices.

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