Samantha Vinograd is a CNN national security analyst. She is a senior adviser at the University of Delaware's Biden Institute, which is not affiliated with the Biden campaign. Vinograd served on President Barack Obama's National Security Council from 2009 to 2013 and at the Treasury Department under President George W. Bush. Follow her @sam_vinograd. The views expressed in this commentary are her own. View more opinion articles on CNN.

(CNN) After months of publicly smearing Lt. Col. Alexander Vindman, it appears President Donald Trump took a final shot at a man who did nothing more than faithfully carry out the duties of his job -- and issued a warning shot to anyone else who dares question him.

According to his attorney, Vindman was fired on Friday from the National Security Council -- a decision that will have adverse impacts for American national security. Later that evening, he also fired the US Ambassador to the European Union, Gordon Sondland, a Trump appointee and Republican donor who gave $1 million to Trump's inaugural committee.

Sam Vinograd

Both men had testified under subpoena before the House Intelligence Committee during impeachment last November. Vindman told the committee that he had listened in (as part of his NSC duties) on President Donald Trump's phone call with the Ukrainian President, and he had been so disturbed by the content of what he heard that he reported it to an NSC lawyer.

Trump made no secret of his anger at Vindman's testimony, and the timing of Vindman's dismissal is likely no coincidence. Acquitted by the Senate on Wednesday, President Donald Trump feels emboldened to act on his every impulse, now that Congressional Republicans have shown him they will not hold him accountable -- no matter the risk.

Vindman was escorted off White House grounds, according to his attorney, and in a manner that was likely intended to publicly embarrass him. His brother Yevgeny Vindman, who also worked on the NSC and is also a lieutenant colonel, was fired as well. (When asked to comment on the departure of the Vindman brothers, NSC spokesman John Ullyot said , "We do not comment on personnel matters.")

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