As President Trump’s impeachment trial speeds to a close, perhaps as soon as Friday, likely without any witnesses, the result looks to be a worst-case scenario.

In the beginning, the president’s lawyers made a relatively benign argument: He didn’t do it. No quid pro quo.

But House managers tried their case too well. Evidence piled up on the Senate floor over the past 10 days that the president withheld military aid to force Ukraine to announce probes of his political foes. And former national security adviser John Bolton’s firsthand account leaked about the quid pro quo.

In response, Trump’s defenders shifted to a far more sweeping, and dangerous, defense. They stepped away from denying misconduct and instead declared that the president can do as he pleases — or, as Trump puts it, that the Constitution gives him “the right to do whatever I want as president.”

It was a tactical move — perhaps the only way to avoid calling Bolton as a witness, by rendering the facts of the case irrelevant — but with grim consequences. Now, when they acquit, senators won’t just excuse Trump’s behavior. They will endorse the belief that a president can do as he pleases — the law be damned.

“If a president did something which he believes will help him get elected — in the public interest — that cannot be the kind of quid pro quo that results in impeachment,” Trump lawyer Alan Dershowitz declared Wednesday.

Another of Trump’s lawyers, Pat Philbin, added that it would be perfectly legal for Trump’s campaign to take as a gift a foreign government’s “credible information of wrongdoing” by a political opponent.

On the Senate floor Thursday, Democratic senators probed for limits to what one called this “insane” doctrine: Could a president take any election help he wants from a foreign government? Could he withhold a city’s disaster aid if the mayor doesn’t endorse him?

“What we have seen over the last couple of days is a descent into constitutional madness,” said Rep. Adam Schiff, the lead House manager.

In the Nixon-Frost interview of 1977, President Richard Nixon uttered the infamous words: “When the president does it, that means it is not illegal.” Now, “we are right back to where we were a half-century ago, and I would argue that we may be in a worse place,” Schiff said. “Nixon was forced to resign. But that argument may succeed here now.”

This is how the stakes have changed during the Senate trial. At first, Republican senators planned to acquit Trump for his behavior. Now they are voting to bless his claim that anything he does is, by definition, legal.

Conservative legal thinkers have tried for decades to demolish the post-Watergate restraints on the presidency. But this demolishes far older ones. The president need no longer yield documents or testimony to congressional oversight. And the president can ignore any law if it helps in his reelection — as long as he believes his reelection is in the public interest. (Dershowitz, in a series of tweets Thursday, denied saying what he said, and his colleagues halfheartedly walked back his claim.)

Is it in the public interest to shut down media outlets Trump regards as “fake news”?

Is it in the public interest for him to ignore court orders that frustrate his agenda?

Could he cancel the election if he thinks his second term is in the public interest?

The Trump White House has already moved to block publication of Bolton’s book, saying its release would harm national security.

The Justice Department decrees that a sitting president can’t be indicted. (Robert Mueller cited that in declining to decide whether to charge Trump.) Now the Senate is saying a president can’t be impeached if he’s acting in his political interests.

Once Republican senators accepted this argument, prospects faded that Bolton would be called as a witness. The trial degenerated into farce.

On Thursday, Sen. Rand Paul (R-Ky.) attempted to unmask a person he suspects of being the whistleblower whose complaint started the impeachment probe by forcing Roberts to read the name. After Roberts refused to play along, Sen. Ron Johnson (R-Wis.) led a backdoor attempt to unmask their suspected whistleblower in another question.

Trump lawyer Jay Sekulow attacked three Democratic senators by name. Trump lawyer Eric Herschmann boasted about prescription drugs and dead terrorists.

But the consequences of this farce are not funny. What will Trump try next now that he knows he can’t be indicted and can’t be impeached, regardless of the legality of his actions?

“God help us,” said Sen. Mark Warner (Va.).

Earlier in the trial, Schiff warned the senators: “Right matters, and the truth matters. Otherwise, we are lost.”

With their votes to acquit, senators will embrace a new concept: Right is whatever the president says it is.

We are lost.

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