Bolton is at best, a 'cooperating witness'-type participant; flipped and essentially given the choice to cooperate on the take down of the Swamp or to go down with them  I agree completely.  Pelosi, Schiff, Nadler, Bidens, etc, etc KNOW whether Bolton is their guy or not. What they don't know perhaps is whether he can be trusted or not (whether he has been flipped or not).  How can they know he's still their guy if they don't know if he can be trusted? What do you think indicates to them that he's still trustable? I pointed out a few things they would have to go by. What more would you expect than those, at this point? It's important to understand that their comms are in tatters. They're forced to trust or not trust, unless they can find a way to communicate safely. Thus the reason to want Bolton in their chambers for questioning.   I think the reasoning that indications that 'Trump doesn't trust Bolton mean that Bolton is theirs' is too superficial  I was perhaps too vague in what I meant, which was that they have to trust that he's still with them. This is why they want to question him.  if you are going to posit that Bolton's role is a willing cooperating part of the Trap, then you have to ask, well, why are the Dems doing what they are doing?  I believe that Bolton is turned. He's a willing cooperative as far as clearing his slate and avoiding jail time by helping Trump. That means he has to play like he's still a black hat.  The idea that as a DS puppet he takes his orders from above and just follows them is not realistic. Their method of operating and communicating has been upset to the point that they have to trust each other more than ever and operate blindly in certain respects when it comes to that trust and knowing what to do. So they rely on cues like Bolton's sudden termination, his tweet about his twitter account being blocked, etc. as signals that he's still on board with them.  The Dems are doing what they're doing because they want to question him, at least in a deposition, to find out where he stands with them, and what use he might still be to them. They don't necessarily want him to testify, but they sure do want to find out if he's still on board.  As you point out, the impeachment is not the goal in and of itself. They want to drag shit out over time and damage Trump's image while they interfere with his agenda, but they also want to cover their asses where crimes are involved because they know Trump is coming for them. They need to talk to Bolton to find out what he knows Trump knows, etc. He's untethered and they need to reel him in if they can. They can't just call him up and talk about this in normal comms. They need a reason to be talking to him. Calling for his testimony gives them that reason.  A couple of points that need to be revisited from my OP:  Bolton was sent by Trump to Kyiv on Aug. 28 to speak with Zelensky. This could have been Bolton's initial test, to see how he handled the situation. Backchannels would have been used by Trump to find out.   This meeting came after the July 10 meeting that Bolton stormed out of when Sondland brought up the idea that Ukraine investigations into Burisma and the Bidens needed to be reopened. (I missed putting this in my OP) Why did Bolton freak out? I would suggest that he was extracting himself from a matter that he didn't have instructions from Trump on how to handle, since it was probably brought up unexpectedly. I believe Sondland might have been trying to lead Trump into a set-up to make his interest in Ukraine appear politically motivated. Good reason for Bolton to leave at that point if he didn't expect it to come up.  Bolton introduced the idea to Democrat Eliot Engel (on Sept. 23) that Yovanovich's removal was improper and needed looking into. I suggested that this led to the rushed impeachment inquiry the very next day. I will also suggest that it was a set-up that Trump initiated for exposing the corruption in the US embassy and by extension Burisma and the Bidens, which came out through the inquiry.   @Paladin_Diver has also pointed out that Bolton was the one who put the Vindmans in place in the NSC. This means that Bolton knew they were plants, and I suggest he informed Trump, who devised a plan to expose and remove them while retaining Bolton's image as a black hat for possible future use.