The MSNBC host Nicole Wallace attacked several right-wing commentators on October 29 for slandering National Security Council European Affairs Expert Lt. Col. Alexander Vindman. Wallace hosts MSNBC’s Deadline: White House. She slammed President Donald Trump’s supporters in the conservative media for doubting the integrity of the decorated officer Lt. Col. Vindman, who was born in Ukraine before emigrating to the U.S. at the age of three.

Vindman deposed before three House Committees on October 28 in a closed session. He testified that he was confident that the Trump White House’s negotiations with Ukraine undermined U.S. national security and made financial aid for Ukraine contingent on finding dirt about Vice President Joe Biden and his son, Hunter Biden.

Vindman said he flagged his concerns about the Ukraine issue on two occasions to senior officials and the National Security Council’s lead attorney.

Wallace tore into Fox News hosts Laura Ingraham and Brian KilmeadeU.C. Berkeley Professor John Yoo and CNN contributor Sean Duffy, calling them “chickenshit.”

Ingraham, Kilmeade, Yoo and Duffy insinuated that Vindman was a Ukrainian double-agent. Yoo claimed, “some people might call [Vindman’s actions] espionage.”

Wallace responded, “except … they know he passed a background check that the president’s daughter and son-in-law didn’t.”

Vindman is an Iraq war veteran, who won a Purple Heart. Yoo’s remark was broadcast live on the Fox News’ show The Ingraham Angle.