Gordon Sondland drew a blank. The details of his July 26 call with President Trump, conducted on a cell phone in a restaurant in Kyiv, Ukraine, are fuzzy, the U.S. ambassador to the European Union testified Wednesday at the fourth day of public hearings in the House impeachment inquiry. Yet he has "no reason to doubt that this conversation included the subject of investigations" Trump allegedly pressured the Ukrainian president to conduct, Sondland said. "Actually, I would have been more surprised if President Trump had not mentioned investigations."

And well he should be, for Trump has spent years yammering on about conspiracies. It would be surprising if he didn't bring that obsession into the White House, if he failed to seize the unique opportunities of his office both to probe at least some of the conspiracy theories he believes to be true — most obviously here, that a hacked DNC server is located in Ukraine — and to conspire himself.

Conspiracy theories are rarely necessary to understand our world — simple self-interest, cruelty, and incompetence usually have more explanatory power — but they are demonstrably attractive to the president. Trump's infamous years-long fixation on former President Obama's birth certificate is just the start.

During the 2016 election, recall, Trump suggested the father of his then-rival, Sen. Ted Cruz (R-Texas), was involved in the assassination of former President Kennedy. He retweeted birther allegations against Cruz and Sen. Marco Rubio (R-Fla.). He claimed the Islamic State attacked him at a campaign rally. He ran ads proposing Syrian refugees "could be ISIS." He promoted a theory that Supreme Court Justice Antonin Scalia was murdered by being smothered with a pillow. He raised the possiblity that a Clinton aide who died in 1993 was also murdered. He had a dalliance with the antivax movement.

And that's just during the last election! In the years before, he proposed climate change might be a Chinese hoax. He called regulations against asbestos a "great con" perpetrated by the mob. In the time since, he has intimated MSNBC host Joe Scarborough murdered an intern. More seriously in terms of national politics, he has repeatedly claimed his loss of the popular vote was due to widespread election fraud. And all three of these lists are inevitably incomplete, for conspiracy theories are a structural component of Trump's mental blueprints. He loves them, and he didn't stop loving them when he got elected president.

The trouble for Trump is that many of the people whose help he would need to turn the administrative branch into his personal conspiracy theory investigation machine are not Trump people. That's not to say, as he likes to complain, that they are never-Trumpers, just that they're career civil servants. Ordinary bureaucrats more than political appointees. They were there before Trump got elected, and they'll probably be there after he leaves office. They are unlikely to be enthusiastic about tracking down evidence for presidential daydreams, especially daydreams already debunked in whole or part by other federal investigations. That's where Rudy Giuliani comes in.

Sondland hinted as much in his testimony Wednesday, describing the president's personal attorney as the tugboat pushing a disinterested barge of federal bureaucracy into conducting Trump's desired bribery scheme with Ukraine. "Secretary [of Energy Rick] Perry, [former Special Representative for Ukraine Kurt] Volker and I worked with Mr. Rudy Giuliani on Ukraine matters at the express direction of the president of the United States," Sondland said. "We did not want to work with Mr. Giuliani. Simply put, we played the hand we were dealt." In Sondland's telling, Giuliani served as a de facto Secretary of the Conspiracy Theories, arranging a quid pro quo with the Ukrainian president at Trump's request.

This is what makes Sondland's testimony so easily plausible to me: Why would a President Trump not retain the conspiracy theory obsession of real estate developer, reality star, and candidate Trump?

Again and again, Trump has called for state investigations of his conspiracy theories du jour. Now he is head of state. Are we supposed to think he just lost interest? Trump's own public comments since taking office show that is not the case. He clearly still thinks in conspiratorial terms.

With Ukraine, it seems Trump saw a chance to get to the bottom of some of his present pet theories, theories he may sincerely believe (or at least hopes to be true). And it also seems he was willing to conspire to get what he wanted.