Jonathan Ernst / Reuters

Ambassador William Taylor’s testimony to House investigators on Tuesday didn’t answer every question about the Ukraine scandal, but it answered the big one: Will President Donald Trump be impeached?

Impeachment is now effectively inevitable. Taylor’s testimony fleshed out the biggest open questions, including whether there was a quid pro quo with Ukraine (there was), what it involved (military aid), and what Trump wanted (investigations of the Biden family and the 2016 election.) Congress has now heard from career civil servants and from political appointees, all telling a similar story, and Taylor removed the last scintilla of doubt. With that, it’s all but impossible to imagine a scenario in which House Democrats don’t vote to impeach the president.

The remaining questions are how much broader the scandal gets, how much worse the details become, and how many—if any—Republicans get on board with impeachment. All of these in turn bear on the ultimate question: whether the Senate might vote to remove Trump.

Though Taylor’s account aligned closely with what was already known, he offered more damning detail than had been available in any previous publicly revealed testimony. Taylor, whom Secretary of State Mike Pompeo appointed as America’s top diplomat in Kiev earlier this year, offered an account of how the administration held up military aid while pressuring Ukraine’s president to mount investigations of a natural-gas company on whose board Vice President Joe Biden’s son sat, and of alleged Ukrainian interference in the 2016 election.

With that, Trump’s defenses have failed on every side. Though the president was reportedly adamant that the exchange not be called a quid pro quo, it doesn’t matter what it was labeled, since it apparently was, in fact, a quid pro quo. Nor does the excuse that Trump was simply trying to use American leverage to fight corruption stand up. The president was seeking to aid his own personal reelection prospects using American statecraft as leverage—a clear abuse of power. (It’s also still possible that the administration broke the law by trying to hold up the funds.) Nor can the president claim ignorance of the scheme, since multiple witnesses have attested to his personal involvement.

“The president used the machinery of government to advance his private interests instead of his own administration’s public policy,” Daniel Fried, a former State Department official in Republican and Democratic administrations, wrote in an email. “Taylor’s statement outlines in devastating detail that there was indeed a presidential-mandated ‘quid pro quo,’ that the substance of the U.S.-Ukrainian relationship was to be made conditional on the Ukrainians acting on behalf of the president’s partisan interests.”

With this information in hand, Democrats have little choice but to vote to impeach. They just have to decide, as my colleague Elaine Godfrey reports, when and on what specific issues.

Any impeachment of a president is an epochal event. Yet this realization is especially surprising because of how quickly it has come. As the drip of evidence has turned into a steady stream over the past two weeks, it’s easy to lose sight of how much the ground has shifted.

Less than one month ago, on September 24, Speaker Nancy Pelosi announced that the House was launching an “official impeachment inquiry.” At the time, that seemed like a potentially risky move. What led Pelosi to act was that a group of moderate Democratic representatives who had been reluctant to impeach announced that they supported an impeachment inquiry—not necessarily articles of impeachment, or a vote to impeach, but a simple inquiry.

A probe made sense, since the public, and Congress, knew very little about the matter in question. There was a whistle-blower complaint about the president’s behavior, and the White House had been refusing to release it, but the substance of the complaint was still mostly unknown. The White House had not yet released the transcript of a call between Trump and Ukrainian President Volodymyr Zelensky. Rudy Giuliani, Trump’s personal lawyer, had been relatively open about his muckraking in Ukraine, but the extent of his hijacking of U.S. foreign policy was unknown. More than half the country opposed impeachment (51.2 percent on average, per FiveThirtyEight), and less than 39 percent of the country backed it.

Since then there’s been a vast shift in both knowledge and opinion. It came slowly at first, and then snowballed. First, the White House released the partial transcript of the July 25 Zelensky call, apparently as a last-ditch effort to forestall the impeachment inquiry. Then came the whistle-blower complaint, packed with incriminating details—yet by the writer’s own acknowledgment, based entirely on second-hand knowledge (though the complaint’s substance was remarkably consistent with the call transcript).

Over the next few days, Trump flailed—threatening the investigators and promising to obstruct the investigation, even as he openly committed the same sin of which he had been accused. But it turned out Trump couldn’t hold the line, and a procession of current and former officials opted to testify to Congress, many under subpoena. Meanwhile, Trump was making it hard for his allies to defend him on other fronts too, from his green light for a Turkish invasion of Syria to his announcement that he would host the Group of Seven summit at his own Trump National Doral resort.

Amid the tumult, public opinion shifted quickly. Within five days of Pelosi’s announcement, support was in the black; it now sits at an even 50 percent in FiveThirtyEight’s average, with some polls showing higher support. Only 43.1 percent oppose impeachment.

Taylor’s testimony offers several leads for House investigators to pursue, and  interviews with other officials have already been scheduled or requested. But there’s no longer a question of whether the House has sufficient material to impeach. Given what they’ve found, Democrats probably couldn’t avoid a vote to impeach even if they wanted to—which some still might.

Republicans are in an even tighter vise. With a few exceptions, elected GOP officials have found it very hard to defend Trump’s behavior substantively. Instead, they have complained about the process, saying that Democrats are too secretive, or attacking Representative Adam Schiff, the most prominent Democrat leading the inquiry. A Daily Caller canvass found that only seven of the 53 Republican senators were willing to rule out voting to remove Trump from office.

That caginess might be wise. Neither side knows how much worse the Ukraine story will get with more testimony, or whether evidence of Trump improperly pressuring other countries might emerge. As the past month demonstrates, a lot can change in a few short weeks. One month ago, it wasn’t clear there’d even be an impeachment inquiry. Today, impeachment itself is a near-certainty.

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