Alexander Semyon Vindman is a retired United States Army lieutenant colonel who served as the Director of European Affairs for the National Security Council (NSC) until 2020. He came to national attention in 2019 as a witness in Congress's impeachment inquiry into Donald Trump during the Trump–Ukraine scandal. In his testimony, he described concerns he had previously reported regarding a call between President Donald Trump and Ukrainian President Volodymyr Zelenskyy that contributed to the abuse of power charge in the first impeachment of Trump.