To impeach Pence, you'd have to start a separate impeachment inquiry. And, even if he's implicated in this, anything Pence has done will look like such a small thing compared to the utter corruption of Trump that no Democrat will want to "waste time" on it and lose focus on the Trump impeachment.
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They censured Clinton when they couldn't convict. And it made little to no difference to how the Clinton White House did business. I largely feel censure is meaningless, and all it can do is anger progressives, and make conservatives smug at the "liberal capitulation." The symbolic nature will be lost on everyone.