Perhaps the most revealing part of the testimony that acting Ukraine Ambassador William B. Taylor Jr. offered to the House impeachment inquiry is an admission of his own ignorance. Asked by a senior aide to Ukrainian President Volodymyr Zelensky two months ago why aid to his country had been halted, Taylor had no answer to give him.

“I was embarrassed that I could give him no explanation for why it was withheld,” Taylor testified.

As collected testimony of inquiry witnesses makes clear, no member of Congress, diplomat or Ukrainian official was ever given a specific reason for the aid being withheld. There were no formal, last-minute stipulations that Ukraine was asked to meet. There was no additional vetting mandated before the aid was released.

That leaves only one reason that the aid was withheld: President Trump’s desired investigations, which he hoped would incriminate former vice president Joe Biden or undermine the probe into Russian interference in the U.S. election.

By the point at which Zelensky’s aide contacted Taylor, money approved by Congress and intended for Ukraine had been on hold for more than six weeks.

Until mid-July, everything had been on track — unremarkable, even. Military aid intended for Ukraine —$250 million — had been authorized in August 2018, appropriated that September and confirmed this May, as Lawfare delineated last month.

The Pentagon issued a news release about it in mid-June. Another $141 million was appropriated in February for the State Department to spend for Ukraine’s benefit. The State Department notified the White House Office of Management and Budget in late June that it intended to pay that money out.

Every box had been checked, but OMB didn’t release the money. Normally a request that money be spent is fulfilled within a matter of days. In this case, though, aid wasn’t released until Sept. 11, nearly two months after it was first held. There are questions, in fact, about the authority the agency had to actually hold the aid for that long.

Taylor and other administration officials learned about the hold on July 18 when an unidentified OMB staffer told a conference call that aid was stopped by order of the president.

The halt came to national attention on Aug. 28, when Politico first reported that it hadn’t moved forward. A senior administration official who spoke with Politico’s reporters claimed that the aid had been stopped because Trump “wants to ensure U.S. interests are being prioritized when it comes to foreign assistance, and is seeking assurances that other countries are ‘paying their fair share.’ ” The official claimed that then-national security adviser John Bolton and Defense Secretary Mark T. Esper were reviewing the aid.

The article spooked the Ukrainians. While there is some reporting that at least some Ukraine officials were aware of the hold earlier that month, Zelensky aide Andrey Yermak on Aug. 29 sent text messages to two senior officials in response to Politico’s reporting. One was special envoy to Ukraine Kurt Volker. The other was William Taylor.

That Taylor had no answer to the question is telling. Yes, that official told Politico that the administration was reviewing the aid to determine if other countries were paying “their fair share” or that “U.S. interests are being prioritized” — a phrase that can now be read as referring to Trump’s desired investigation into Joe Biden under the guise of battling “corruption.” But Taylor’s testimony suggests that this was a cover.

Asked if he was aware of any actual preconditions for withholding the aid, Taylor said he'd only heard of one.

“The only thing I heard was that there was a request — and I’m not sure who it came from, but it may have come from the [National Security Council] to the Defense Department for an evaluation of the assistance to be sure that it was being well-spent and it was effective,” Taylor said. “And the Defense Department came back very quickly with the conclusion that it was.”

That’s included in the Politico article, in fact, with a Defense Department official stating that “the department has reviewed the foreign assistance package and supports it.” Coming out of the meeting on July 18, Taylor said, officials from the State Department and perhaps Defense even considered moving forward with the aid outside of OMB — something that he described as possibly unprecedented and a “big decision for them.” This didn’t happen.

Bolton, Taylor testified, was not only not conducting a review of the funds before they were distributed but instead was “trying, with the two secretaries and the director of the CIA, to get this decision reversed.” One of those secretaries was Secretary of State Mike Pompeo and the other was Esper.

Asked if the government had eliminated concerns about corruption before releasing the aid, Taylor pointed to the established process that transpired months earlier.

“My understanding is those conditions were met,” he said. “On this specific one I’m not sure. I think so.”

This again is the acting ambassador to Ukraine operating in the dark on why aid had been halted and suggesting that he’d heard nothing further about the need to establish Ukraine’s anti-corruption efforts, much less how “U.S. interests were being prioritized” more generally. If there were benchmarks that Ukraine was supposed to hit to receive the aid, he wasn’t told what they were.

The other person that Yermak contacted about it was Volker, the special envoy. Volker was part of what Taylor referred to as the “irregular channel” of decision-making on Ukraine along with Energy Secretary Rick Perry and Ambassador to the European Union Gordon Sondland, a group that called itself the “three amigos” and which was tasked by Trump with working through his personal attorney Rudolph Giuliani on Ukraine issues.

When Volker was asked by impeachment investigators why the aid was halted, he, too, indicated that he didn't know.

“Nobody ever gave a reason why,” he said.

“With something this serious and bipartisan and significant, there should be an explanation, right?” committee Chairman Rep. Adam B. Schiff (D-Calif.) asked.

“There should have been,” Volker said, “but there wasn't.”

Volker and Taylor weren’t alone. Members of Congress didn’t know why the aid was halted either. Senate Majority Leader Mitch McConnell (R-Ky.) wasn’t told. The Ukrainians didn’t know. The aid just stopped.

Shortly after the Politico story broke, things started to gel. On Aug. 30, Sondland suggested to Sen. Ron Johnson (R-Wis.) that the reason aid was being withheld was because Trump wanted public investigations into Biden, Biden’s son and the origins of the Russia probe. On Sept. 1, Sondland met with Yermak and directly linked those two things — a meeting Sondland only admitted to after other testimony (including Taylor’s) made clear that he’d done so.

Sondland claims that this wasn't a condition articulated by Trump but, instead, that he just sort of came to the conclusion that aid wouldn't be released until investigations began.

“[By] the beginning of September 2019,” he wrote in an amendment to his original testimony, “and in the absence of any credible explanation for the suspension of aid, I presumed that the aid suspension had become linked to the proposed anti-corruption statement” — that is, the public announcement of investigations.

This Sondland-Yermak conversation quickly made its way back to Taylor, who expressed alarm. In his own testimony, Taylor described having spoken with Sondland after Sondland informed him that he'd had multiple conversations with both Trump and Zelensky.

“What came from Sondland when he told me this story was President Trump said it was not a quid pro quo. Ambassador Sondland said that he had talked to President Zelensky and Yermak and told them that, although this was not a quid pro quo, if President Zelensky did not clear things up in public, we would be at a stalemate.”

In other words, no aid.

Both Volker and Sondland used the same analogy in explaining what was needed in order for Ukraine to get the aid. Trump was a businessman, Taylor was told, and therefore would make sure he got the goods he was supposed to be getting before signing any checks for payment.

“They both understood that if President Trump was going to sign the check for military assistance,” Schiff asked, “then they needed to pay up first and that pay-up was a public declaration of these two political investigations?”

“That was the parallel,” Taylor replied.

There was no other reason offered for the aid being withheld. Nor was that stipulation ever met, but not because Trump had a change of heart. It was eventually released on Sept. 11 after The Washington Post editorial board raised questions about aid being withheld to spur Ukrainian investigations and after a group of Democratic legislators announced an investigation into why the aid had been stopped.