On Tuesday, House Speaker Nancy Pelosi endorsed impeachment proceedings against President Donald Trump. Trump will now face a long-anticipated inquiry, but the politics around such an extraordinary constitutional remedy to what may well be a delinquent presidency have been dramatically altered by recent events.

A new bombshell allegation involving Trump, Joe Biden and the president of Ukraine has shaken loose some recalcitrant Democrats, including Speaker Nancy Pelosi, leading them to accept, however reluctantly, the validity of an impeachment probe.

Democratic lawmakers have endured nearly two years of scorn over their reluctance to pursue the impeachment of this president. They are owed an apology.

These more cautious Democratic lawmakers have endured nearly two years of scorn from their more passionate colleagues over their reluctance to pursue the impeachment of this president. They are owed an apology. Trump’s political allies are now doing whatever they can to frame this inquiry as an illegitimate expression of unhinged partisanship, and they do not lack for supporting evidence. For that, impeachment-crazed Democrats have no one to blame but themselves.

Spin aside, the details of the incident that kicked off this tipping point scandal are, for the most part, no longer in doubt. In a July phone call with Ukrainian President Volodymyr Zelenskiy, the American president urged his counterpart in Kyiv to investigate one of his domestic political adversaries, Joe Biden, and Biden’s family. The president has admitted as much, and a rough transcript of that call released by the White House confirms it.

The outstanding question is whether that sordid request was accompanied by an inducement in the form of withheld military assistance previously authorized by Congress. Trump has denied that military assistance to Ukraine, which had been inexplicably waylaid over the summer, had been held in reserve to strong-arm Zelenskiy. But the aid was withheld, and the new Ukrainian president tasked with fighting a war against Russian proxy forces on his country’s soil knew it. When Trump made mention of that stalled assistance on his call with Zelenskiy, it was surely received as a loaded reference, especially given the pressure Trump’s lawyer Rudy Giuliani was separately putting on Zelenskiy to investigate Biden.

For all his denials, the president also defended the legitimacy of actions he claimed he never took: “Why would you give money to a country that you think is corrupt?” Trump asked. And though the president insists he did not threaten Ukraine’s president outright, he also insists that “it would probably, possibly have been okay if I did.”

An “impeachable offense” is really whatever Congress determines it to be. But even by a layman’s definition, the misuse of executive authority to pressure a foreign government in pursuit of domestic political advantage is corruption. Moreover, if that effort constituted a solicitation of assistance from a foreign government (labor with presumed monetary value) to advance Donald Trump’s re-election prospects, it could be construed as a criminal violation of federal election law.

Because impeachment is a political act, not a legal one, the public must be convinced of its validity if it is to succeed. The problem Democrats face in that effort is that the party’s members have argued repeatedly over the past two years that Trump was committing impeachable offenses left and right.

In 2017, nearly 60 House Democrats voted in favor of impeaching the president for bringing “disrepute, contempt, ridicule and disgrace on the presidency.” The articles of impeachment ranged from the president’s offensive remarks on the violent clash between white supremacists and counterdemonstrators in Charlottesville to his objection to NFL players kneeling for the national anthem.

That same year, Rep. Brad Sherman introduced an absurd impeachment resolution alleging that Trump’s decision to fire his FBI director violated the Constitution. Rep. Al Green has sponsored a series of impeachment articles, among them the claim that Trump calling Rep. Frederica Wilson “wacky” and his foul-mouthed assessment of equatorial nations were gross misuses of presidential authority. A total of 95 Democrats voted to impeach the president for calling illegal migrants and asylum-seekers “invaders” and saying that four freshman Democrats of color should “go back” to other countries. And of course, for progressive firebrands and partisan liberal pundits, the Mueller report’s findings that Trump did not conspire with a foreign power and had tried but failed to intervene in the investigation into the events of 2016 constituted the gravest of constitutional crimes.

Those Democrats who previously demurred were correct to believe that the politics of impeachment favored the president. A Monmouth University poll in late August found, for example, that only 35 percent supported impeaching the president, with 61 percent opposed. A Quinnipiac poll released Wednesday confirms that a majority — 57 percent — continue to oppose the president’s impeachment. These polls likely reflect appropriate skepticism over the value of impeachment as a response to allegations centered on far more ambiguous claims of presidential impropriety than the one that is being litigated now.

But Democrats’ trigger-happy record will be an obstacle to convincing voters who are not already convinced of Trump’s unfitness. What’s more, it will affirm the preconception among some Republicans that these new charges against the president are frivolous and myopic as all the others. The compelling illogic of negative partisanship will do the rest of the work, and Republican lawmakers whose electoral fortunes are tethered to Trump’s will stand with their voters in defense of the president. In the absence of some unambiguous smoking gun, that is unlikely to change, no matter what impeachment proceedings uncover.

But Democrats’ trigger-happy record will be an obstacle to convincing voters who are not already convinced of Trump’s unfitness.

So what happens if Trump is impeached by the House, acquitted in the Senate and re-elected nonetheless next November? Impeachment will remain a remedy for presidential misconduct only in theory. In practice, that constitutional maneuver will have been neutralized for all but the gravest and most unequivocal episodes of mismanagement. Democrats, sensing that the strike against Trump backfired, will have lost the ultimate instrument of deterrence. Vindicated at the polls, the president’s conduct is certain to be even more reckless. And unless you count the power of subpoena and theatrical committee hearings as a check on the presidency, Trump will be unleashed like never before, imbued with a sense of invulnerability.

You can see why the party’s leadership in the House was keen to avoid this outcome. Democrats will make significant sacrifices in pursuit of the president’s impeachment, and the risks are serious.

Yet there can be no question that the American people deserve to know whether their president would sacrifice their interests in service to his own personal glory. If the answer to that question is yes, however, the remedy will not be the president’s removal from office by the U.S. Senate but by voters on Nov. 3, 2020. And, if these allegations amount to what they appear to be, Trump will have earned that fate.

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