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Regular readers of this newsletter may remember my criticisms of both Robert Mueller and James Comey. I think Mueller ducked the tough decisions he faced at the end of his investigation and issued an ineffectual report that failed to come to clear conclusions. And Comey — during the 2016 investigation of Hillary Clinton’s email use — put a higher priority on preserving his own reputation for being above partisan politics than on doing the right thing.

The impeachment hearings of the last week got me thinking about this recent history, because the witnesses, like Marie Yovanovitch, have shown a strength that Mueller and Comey did not. Those witnesses have been willing to subject themselves to unfair criticism for being partisan in order to defend the country’s ideals. We all owe them a debt of gratitude.

[Listen to “The Argument” podcast every Thursday morning, with Ross Douthat, Michelle Goldberg and David Leonhardt.]