National Security Council aide Lt. Col. Alexander Vindman is sworn in to testify before the House Intelligence Committee on Capitol Hill in Washington, Tuesday, Nov. 19, 2019, during a public impeachment hearing of President Donald Trump's efforts to tie U.S. aid for Ukraine to investigations of his political opponents. Credit: Andrew Harnik | AP

Last Tuesday morning’s installment of the House’s impeachment hearings wasn’t expected to produce sensational headlines. The witnesses — Lt. Col Alexander Vindman, a Ukraine expert on the National Security Council staff, and Jennifer Williams, an adviser on Russia to Vice President Mike Pence — weren’t expected to enlarge in significant ways on their previous testimony in closed sessions.

In fact, the hearing did produce two nuggets of news.

The first is that Vindman was offered the position of defense minister of Ukraine, his ancestral home. (He declined, and reported the approach to his superiors in Washington even though he found the idea “rather comical.”)

But the more important news — related to this revelation — is that Republicans on the Intelligence Committee made the decision to attack Vindman’s character. It backfired spectacularly.

It’s easy to see why the Republicans, who see themselves as President Trump’s collective defense counsel, would go after Vindman. As he noted in his powerful opening statement, Vindman complained to the counsel of the National Security Council about Trump’s phone call with Ukrainian President Volodymyr Zelenskiy. Vindman did so, he said, because he thought it was “improper for the president of the United States to demand a foreign government investigate a U.S. citizen and political opponent.”

Still, it was folly for the Republicans to try to besmirch a witness who clearly seemed to be acting out of patriotic, not political motives. (If anything, Vindman fortified that image by sometimes not giving Democratic questioners the answers they wanted.)

Not only did the Republicans suggest that Vindman might be a leaker and someone with an exaggerated sense of his own importance in foreign policy. But the questions about the offer of the defense minister post, posed by Republican counsel Steve Castor, also slyly impugned his patriotism.

In an especially ugly turn, Castor asked Vindman whether Oleksandr Danylyuk, the adviser to Zelenskiy who made the job offer, spoke in Ukrainian or English. Vindman responded: “He is an absolutely flawless English speaker who was speaking in English.”

It was a priceless putdown.

The dual-loyalty insinuation is likely to appeal to Trump loyalists who imbibe on Fox News commentary. But any viewer with a modicum of open-mindedness could only be repulsed by the way Vindman was treated.

Michael McGough is the Los Angeles Times’ senior editorial writer, based in Washington, D.C.