In the end, the story told by the two articles of impeachment approved on Friday morning by the House Judiciary Committee is short, simple and damning: President Donald Trump abused the power of his office by strong-arming Ukraine, a vulnerable ally, holding up hundreds of millions of dollars in military aid until it agreed to help him influence the 2020 election by digging up dirt on a political rival.

When caught in the act, he rejected the very idea that a president could be required by Congress to explain and justify his actions, showing “unprecedented, categorical and indiscriminate defiance” in the face of multiple subpoenas. He made it impossible for Congress to carry out fully its constitutionally mandated oversight role, and, in doing so, he violated the separation of powers, a safeguard of the American republic.

To quote from the articles, “President Trump, by such conduct, has demonstrated that he will remain a threat to national security and the Constitution if allowed to remain in office, and has acted in a manner grossly incompatible with self-governance and the rule of law.”

The case now moves to the full House of Representatives, which on Wednesday will decide, for just the third time in the nation’s history, whether to impeach a president.

To resist the pull of partisanship, Republicans and Democrats alike ought to ask themselves the same question: Would they put up with a Democratic president using the power of the White House this way? Then they should consider the facts, the architecture and aspirations of the Constitution and the call of history. In that light, there can be only one responsible judgment: to cast a vote to impeach, to send a message not only to this president but to future ones.

By stonewalling as no previous president has, Donald Trump has left Congress with no choice but to press ahead to a Senate trial. The president insists he is innocent of any wrongdoing, yet he refuses to release any administration documents or allow any administration officials to testify — though, if his assertions are in fact true, those officials would presumably exonerate him. He refused to present any defense before the House whatsoever, asserting a form of monarchical immunity that Congress cannot let stand.

It’s regrettable that the House moved as fast as it did, without working further through the courts and through other means to hear from numerous crucial witnesses. But Democratic leaders have a point when they say they can’t afford to wait, given the looming electoral deadline and Mr. Trump’s pattern of soliciting foreign assistance for his campaigns. Even after his effort to extract help from Ukraine was revealed, the president publicly called on China to investigate his rival. Asked as recently as October what he hoped the Ukrainians would do in response to his infamous July 25 call with their president, Mr. Trump declared: “Well, I would think that, if they were honest about it, they’d start a major investigation into the Bidens. It’s a very simple answer.”

Barring the persuasive defense that Mr. Trump has so far declined even to attempt, that simple answer sounds like a textbook example of an impeachable offense, as the nation’s framers envisioned it.

A president “might pervert his administration into a scheme of peculation or oppression,” James Madison said of the need for an impeachment clause. “He might betray his trust to foreign powers.”

Madison and his fellow framers understood that elections — which, under normal circumstances, are the essence of democratic self-government — could not serve their purpose if a president was determined to cheat to win.

As the constitutional scholar Noah Feldman testified before the Judiciary Committee last week, “Without impeachment, the president would have been an elected monarch. With impeachment, the president was bound to the rule of law.”

At the same time, the framers were well aware of the dangers inherent in impeachment. That’s why they made it a two-step process: First is the House’s vote on impeachment, which is akin to an indictment and requires only a majority to pass. Second is a trial in the Senate, which decides the president’s ultimate fate, and thus has a much higher bar to clear — two-thirds of senators must vote to convict and remove the president from office.

So far, Republican legislators have shown little sign of treating this constitutional process with the seriousness it demands.

By stonewalling as no previous president has, Donald Trump has left Congress with no choice but to press ahead to a Senate trial.

Instead, they have been working overtime to abet the president’s wrongdoing. They have spread toxic misinformation and conspiracy theories to try to justify his actions and raged about the unfairness of the inquiry, complaining that Democrats have been trying to impeach Mr. Trump since he took office.

No doubt some Democrats were too eager to resort to impeachment before it became unavoidable. Mr. Trump has been committing arguably impeachable offenses since the moment he entered the Oval Office, including his acceptance of foreign money at his many businesses; his violations of campaign-finance law in paying hush money to a woman who claimed to have had a sexual affair with him; and, of course, his obstructions of justice in the Russia investigation, which were documented extensively by the special counsel, Robert Mueller.

Democrats could have pursued impeachment in any or all of these cases, but for various reasons decided not to. That changed in September, when a whistle-blower’s complaint, initially suppressed by the Justice Department, revealed the outline of Mr. Trump’s Ukraine scheme. That made it impossible to ignore the president’s lawlessness because it sounded an alarm that he was seeking to subvert the next election, depriving the voters of their right to check his behavior.

The Republicans’ most common defenses of Mr. Trump’s behavior fall flat in the face of the evidence.

There is, above all, the summary of the July 25 phone call between Mr. Trump and Volodymyr Zelensky, the Ukrainian president. Mr. Trump still insists that summary exonerates him. It doesn’t — which is why White House officials promptly locked it in a special computer system.

Then there is the sworn testimony of multiple government officials, including several appointed by Mr. Trump himself, all of whom confirmed the essential story line: For all the recent claims about his piety regarding Ukrainian corruption, Mr. Trump did not “give a shit about Ukraine.” He only wanted the “deliverable” — the announcement of an investigation into the Bidens, and also into a debunked theory that Ukraine interfered in the 2016 election.

The argument that Mr. Trump cared about anything other than hurting Joe Biden and helping himself is undercut by several facts. Even though calling on the Ukrainians to fight corruption was part of his prepared talking points, he never mentioned the subject in his calls with Mr. Zelensky; he also didn’t hold up the military aid in 2017 or 2018, even though everyone knew about Hunter Biden’s Ukraine connection at the time. (What changed this year? Joe Biden emerged as his leading Democratic opponent.) By the time Mr. Trump intervened to block the money for Ukraine, the Defense Department had already certified that Ukraine had made enough progress fighting corruption to qualify for this year’s funds.

Republicans and Democrats ought to ask themselves the same question: Would they put up with a Democratic president using the power of the White House this way?

Without any substantive defense of Mr. Trump’s behavior, several Republicans have taken to arguing that he committed no actual crime, and so can’t be impeached for “high crimes and misdemeanors.” Putting aside a strong case that Mr. Trump has, in fact, broken at least one law, this isn’t how impeachment works. “High crimes” refers to severe violations of the public trust by a high-ranking official, not literal crimes. A president can commit a technical crime that doesn’t violate the public trust (say, jaywalking), and he can commit an impeachable offense that is found nowhere in the federal criminal code (like abuse of power).

Republicans’ sole remaining argument is: “So what? It wasn’t that big a deal.” Or, as acting White House chief of staff, Mick Mulvaney said in October, “Get over it.” This stance at least has the virtue of acknowledging the president’s vice, but that doesn’t make it O.K.

Assuming Mr. Trump is impeached, the case will go to the Senate, where he will have the chance — on far more friendly territory — to mount the defense he refused to make to the House. Rather than withholding key witnesses, he should be demanding sworn appearances by people like Mike Pompeo, the secretary of state, and John Bolton, the former national security adviser.

As recently as a few weeks ago, some Republicans seemed to want to get to the bottom of things. Even Mr. Trump’s footman, Senator Lindsey Graham, said, “If you could show me that, you know, Trump actually was engaging in a quid pro quo, outside the phone call, that would be very disturbing.”

The time for such expressions of public spirit has, apparently, passed. “I’ve written the whole process off,” Mr. Graham said during the impeachment hearings. “I think this is a bunch of B.S.”

Mitch McConnell, the Senate majority leader, says there will be “no difference between the president’s position and our position in how to handle this,” as he told Sean Hannity of Fox last Thursday. Before the House had cast a single vote on impeachment, Mr. McConnell said there was “no chance” the Senate would vote to convict.

For now, that leaves the defense of the Constitution, and the Republic, to the House of Representatives.

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