After two days of earlier hearings laid out the contours of a broad pressure campaign on Ukraine by Mr. Trump and his allies, the accounts by Colonel Vindman and Ms. Williams brought the public phase of the impeachment inquiry inside the White House for the first time. For Colonel Vindman in particular, the testimony amounted to a remarkable act of public criticism of the president by a White House employee.
The colonel, who came to the United States as a refugee at 3, referred to his family’s history in Ukraine, a former Soviet republic, noting that in Russia, “offering public testimony involving the president would surely cost me my life.”
Addressing his father, who he credited with “the right decision” in leaving the Soviet Union to seek refuge in the United States 40 years ago, Colonel Vindman said, “Do not worry, I will be fine for telling the truth.”
But the White House and its Republican allies on Capitol Hill moved quickly to try to discredit Colonel Vindman, questioning his loyalty to the country and his professionalism.
As he sat in the stately House Ways and Means Committee Room that is the backdrop for the impeachment hearings, the official, taxpayer-funded Twitter account of the White House posted a critical quote in which Timothy Morrison, his former boss at the National Security Council, questioned Colonel Vindman’s “judgment.”
Mr. Morrison, the council’s former senior director for Russia and Europe, was testifying in a second session on Tuesday afternoon alongside Kurt D. Volker, the former United States special envoy to Ukraine.
Representative Jim Jordan of Ohio, a top Republican ally of the president’s, cited Mr. Morrison’s comment and criticism from Fiona Hill, Mr. Vindman’s former boss at the National Security Council.