[A] strong and independent Ukraine is critical to U.S. national security interests because Ukraine is a frontline state and a bulwark against Russian… - Alexander Vindman

[M]y simple act of appearing here today, just like the courage of my colleagues who have also truthfully testified before this committee, would not be tolerated in many places around the world. In Russia, my act of expressing concern to the chain of command in an official and private channel would have severe personal and professional repercussions, and offering public testimony involving the President would surely cost me my life.
I am grateful to my father—for my father's brave act of hope 40 years ago and for the privilege of being an American citizen and public servant, where I can live free, free of fear for mine and my family's safety.

In the spring of 2019, I became aware of two disruptive actors... Ukraine's then-prosecutor , and former Mayor Rudolph Giuliani, the President's personal attorney, promoting false narratives that undermined the United States' Ukraine policy. The NSC and its interagency partners, including the State Department, grew increasingly concerned about the impact that such information was having on our country's ability to achieve our national security objectives.

On July 10, 2019, , the Secretary of the National Security and Defense Council for Ukraine, visited Washington, D.C. for a meeting with National Security Advisor Bolton. Ambassadors Volker and Sondland also attended, along with Energy Secretary Rick Perry.
The meeting proceeded well until the Ukrainians broached the subject of a meeting between the two presidents. The Ukrainians saw this meeting as critically important... Amb. Sondland started to speak about Ukraine delivering specific investigations in order to secure the meeting with the President, at which time Ambassador Bolton cut the meeting short.
Following this meeting, there was a scheduled debriefing during which Amb. Sondland emphasized the importance that Ukraine deliver the investigations into the 2016 election, the Bidens, and Burisma. I stated to Amb. Sondland that his statements were inappropriate, that the request to investigate Biden and his son had nothing to do with national security, and that such investigations were not something the NSC was going to get involved in or push. Dr. Hill then entered the room and asserted to Amb. Sondland that his statements were inappropriate.
Following the debriefing meeting, I reported my concerns to the NSC’s lead counsel. Dr. Hill also reported the incident to the NSC’s lead counsel.