The Situation Room With Wolf Blitzer

Ex-ambassador testified Ukrainian official told her it was "dangerous" to engage with Giuliani; Warned by Ukrainian official to "watch my back"; Ex-State department official testifies he resigned over diplomats being used to advance political objectives; Ex-ambassador testified diplomat Sondland suggested she praise Trump: "You need to go big or go home"; Trump: "The whistleblower should be revealed"; Trump loses appeal to keep taxes from New York grand jury; Four White House officials defy impeachment subpoenas; Mueller documents show Manafort pushed Ukraine conspiracy theory; Bennet looking to qualify for next presidential debate; Testimony: Ex-Pompeo adviser testified State department official felt "bullied" to not cooperate with impeachment probe; White supremacist accused of synagogue bomb plot; German city declare "Nazi emergency" over rising extremism; Accused Russian spy Maria Butina speaks out via Knit