WASHINGTON — A White House aide says that he recognizes that what he is doing — testifying before Congress — would not be tolerated in many other countries.

Lt. Col. Alexander Vindman says in Russia, for example, his “act of expressing my concerns to the chain of command in an official and private channel” would have cost him his life.

Vindman, dressed in uniform, testified that he felt Trump’s request on a July 25 call to a new Ukrainian leader to investigate a political rival was “improper.”

The U.S. Army official is an immigrant from Ukraine. He said that he is grateful his father came to the United States some 40 years ago, a place “where I can live free of fear for mine and my family’s safety.”

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He then spoke to his late father, saying “Dad, my sitting here today ... is proof that you made the right decision 40 years ago to leave the Soviet Union.”