During Wednesday's House impeachment hearing, constitutional law professor Jonathan Turley hit upon what might be the most compelling argument against impeaching the president: You don't want to stoop to President Trump's level, do you?

"I get it: You're mad," Turley, who teaches at George Washington University, told the House Judiciary Committee. "The president's mad. My Republican friends are mad. My Democratic friends are mad. My wife is mad. My kids are mad. Even my dog seems mad. And Luna is a goldendoodle, and they don't get mad."

He went on: "So we're all mad. Where's that taken us? Will [a] slipshod impeachment make us less mad, or will it only give an invitation for the madness to follow in every future administration?"

Trump, of course, is famously fueled by grievance — he might not be president if not for his preternatural hypersensitivity to slights, and his ability to persuade millions of voters that he shares their own sense of injury. So it is more than a little ironic that Turley and Republicans, having reaped the benefits of Trump's own petulance, are now cautioning Democrats against acting out of anger.

Irony aside, this argument fits a pattern of double standards. Defenders of the president who sought to undermine the American electoral process now say his fate should be left up to voters. A president who has gleefully smashed presidential norms now demands that Democrats rigorously observe precedent. He openly accepts and solicits the intervention of foreign countries in U.S. elections, yet declares that American politics should stop at the water's edge when he does the country's business abroad.

Turley's stance on the issue might be less than principled. After all, his Wednesday testimony marked a sharp reversal of his stance from when he testified during Bill Clinton's impeachment hearings 20 years ago. But most importantly, this is just more of Trump's "heads-I-win-tails-you-lose" special pleading — if not for double standards, the president might have no standards at all — and Democrats are right to disregard it.

If Democrats are as angry as Turley suggests, though, it is precisely because of the Republican tendency to tear and bend the rulebook to the GOP's advantage while insisting on strict adherence from their rivals. Think about the last few years. Democrats watched Senate Majority Leader Mitch McConnell (R-Ky.) make up new precedents to deprive President Obama of a Supreme Court appointment — then decide it was no longer applicable when it didn't serve his party. They endured a loss as Trump won the presidency while inviting Russian intervention and despite losing the popular vote. And then they discovered the president had used his office to tilt the balance of the 2020 elections even more. It was that last act, of course, that finally moved Democrats to pursue impeachment.

Despite Turley's assertions, then, Trump's anger and Democrats' anger are not of the same caliber.

Trump is angry because he forever craves a respect he cannot earn — not from late night hosts, not from The New York Times, and certainly not from other world leaders, whose videotaped mockery sparked the president's premature exit Wednesday from the NATO summit. Democrats are angry because they believe their ability to participate fully in democracy is being robbed from them. The first form of anger is born of narcissism, the other of righteous indignation.

This impeachment process, of course, takes place in the context of the larger "resistance" to Trump's presidency — and that resistance has been, in part, an effort to preserve institutions and traditions that have largely served America well over the last two centuries. True to form, Republicans are attempting to defend Trump by weaponizing those traditions, insisting that others adhere to those standards while they themselves trample all over them.

Impeachment thus represents an opportunity — perhaps the last one — for Democrats to preserve those old standards without stooping to Trump's rule-smashing level. The House of Representatives is following the law and Constitution. The president cannot credibly say the same. We are not all Trumpists, after all.

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