Though Republicans noted that Trump has the authority to recall any ambassador at any time — a fact Democrats didn’t dispute — Yovanovitch left them with a question they similarly declined to address.

“I do wonder,” she mused, “why it was necessary to smear my reputation.”

If Yovanovitch’s testimony to impeachment investigators revealed anything, it’s that the president’s defenders didn’t share his limitless capacity to tear down his critics. Furthermore, the Republicans’ unwillingness or inability to undermine Yovanovitch’s narrative underscores the tremendous difficulty they face in mounting a factual defense against impeachment.

Republicans appeared particularly hamstrung by the sympathetic nature of a witness like Yovanovich, who has won virtually unanimous admiration from her colleagues in nearly every facet of the federal government, including among Trump’s own appointees.