In the aftermath of the Watergate scandal and Richard Nixon's resignation, a three-word phrase became a staple of the political discourse: "The system worked." It was generally meant to be reassuring at a time of great uncertainty, as Americans confronted unprecedented and tumultuous circumstances -- including a new president who'd never been elected to national office.

The idea, however, that the system had worked wasn't just intended to placate; it was rooted in core truths. A corrupt president had abused the powers of his office, but under our system, his misdeeds were exposed -- through quality journalism, congressional scrutiny, and the revelations of administration officials who were committed to bringing the truth to light.

The people's Congress took the allegations seriously and pursued vigorous oversight. When matters went before the courts, jurists largely ruled impartially. In time, when the sitting president's guilt became undeniable, members of his own party grudgingly told their corrupt leader that he had no choice but to exit the stage.

The system, in other words, worked. There were institutions in place with a duty to deal responsibly with a pernicious actor, and those institutions did what they were designed to do, to the public's benefit.

Nearly a half-century later, as Donald Trump's abuses of power and illegal scheme came to light, that same system clearly did not work. It was put to the test, and it failed.

Vox's Zack Beauchamp wrote an assessment that rang true.

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Donald Trump's impeachment acquittal is a warning sign that something has gone deeply wrong in our political system. It shows a kind of subtle corruption of the law that has, in other countries, led to the decline and fall of their democratic systems in their entirety. Senate Republicans didn't violate the Constitution's rules for holding an impeachment trial. They adhered fairly reasonably to the letter of the law and can credibly claim they did all that was legally required of them. But this was a sham trial, one whose outcome was never seriously in doubt.

For much of the last couple of months, there was bipartisan agreement that the Senate itself, and not just the president, was on trial. Is anyone seriously prepared to argue that the institution -- which used to describe itself as the "World's Greatest Deliberative Body" -- was acquitted?

To be sure, our political system did not suffer a comprehensive breakdown. As was the case with Watergate, Americans saw relevant players -- including impressive journalists, dogged House Democratic investigators, and Trump administration officials who were willing to testify to the truth -- fill their proper roles. Elements of the system worked as designed.

But nearly every member of the president's party had a different agenda in mind. Their goal was to shield Donald Trump from accountability, and they took every possible step to ensure that outcome.

Holding the first ever Senate impeachment trial without any witnesses? Sure. Moving the goalposts in response to every new damaging revelation? No problem. Embracing evolving and contradictory standards? Absolutely. Rejecting powerful and reliable evidence, even after it's presented on a silver platter? Sounds good. Accepting radical legal theories that they would never tolerate if peddled by lawyers representing a Democrat? Yes. Allowing the White House to refuse any and all attempts at cooperating with a legitimate investigation, including hiding relevant documents and witnesses? Of course.

Acknowledging the president's guilt, but voting to acquit anyway? Count GOP senators in.

We're left with a dynamic in which a sitting president has not only gotten away with abuses on a historic scale, but who's also effectively been told that it's within his power to cheat in his re-election campaign, even if that means using governmental levers to coerce foreign governments into assisting his campaign.

Similarly, that same president, whose authoritarian instincts have long been plain, has learned that he can't be indicted and he can't be removed from office, because his party won't allow it. The result is a toxic recipe.

As Ezra Klein recently noted, "If Republicans in Congress can't act like members of Congress first and Republicans second, then the system's fundamental design stops working."

As the world witnessed yesterday afternoon, Donald Trump was acquitted yesterday. Let no one say the same of our nation's political system and Republicans' role in it.

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