Earlier this week, Donald Trump published a tweet suggesting he’d “never even heard of” Lt. Col. Alexander Vindman, the top expert on Ukraine on the White House National Security Council. At first blush, that didn’t make any sense: how could the president, who’s been deeply engaged on U.S. policy toward Ukraine for months, not know his own top Ukrainian expert?

Yesterday, the answer to that question came into focus, though the answer wasn’t altogether satisfying.

After Ukrainian President Volodymyr Zelensky’s inauguration in May, Vindman was eager to brief Donald Trump on the implications of the change in leadership in Kyiv. Politico reported, however, on why that did not happen.

[H]e was instructed “at the last second” not to attend the debriefing, Vindman told lawmakers, because Trump’s advisers worried it might confuse the president: Trump believed at the time that Kashyap Patel, a longtime Nunes staffer who joined the White House in February and had no discernible Ukraine experience or expertise, was actually the NSC’s top Ukraine expert instead of Vindman. Vindman testified that he was told this directly by his boss at the time, NSC senior director for European and Russian affairs Fiona Hill.

It’s an amazing dynamic, which helps shed new light on just how dysfunctional Trump’s West Wing is. If the National Security Council’s top Ukrainian expert briefed the president, Trump might have become “confused” – not by the information Vindman was sharing, but by the fact that the president was under the impression that an entirely different person was the White House’s top Ukrainian expert.

That other person, Kashyap Patel, is an acolyte of Republican Rep. Devin Nunes, and according to Vindman, Patel “misrepresented” himself to Trump in order to help guide the White House’s policy toward Ukraine.

No wonder the president has “never even heard of” Alexander Vindman. If he’d walked into the Oval Office and introduced himself as Trump’s top Ukrainian expert, the president would’ve wondered what happened to the other guy.

Of course, the larger question is why in the world Trump was listening to a former Nunes aide who (a) didn’t have any background on Ukraine policy; (b) wasn’t talking to Ukraine experts at the State Department and Pentagon; and (c) wasn’t talking to the National Security Council’s expert on Ukraine.

The Politico report added, “Vindman also testified that he was told Patel had been circumventing normal NSC process to get negative material about Ukraine in front of the president, feeding Trump’s belief that Ukraine was brimming with corruption and had interfered in the 2016 election on behalf of Democrats…. It’s still not clear what materials Patel was giving Trump, or where he was getting them.”

This is not how a functioning White House is supposed to work.