In his star turn in the Senate well Monday, Harvard Law professor emeritus Alan Dershowitz at first delivered an account of executive power that, while extreme and wrongheaded, seduced a cadre of Senate Republicans.

Then Wednesday night he drove the car over the cliff, and arguably took himself out of relevance to the Senate’s decision-making.

After Dershowitz’s presentation Monday, a series of Republican senators — including Rand Paul (Ky.), John Cornyn (Tex.) and Ron Johnson (Wis.) — took to the airwaves to endorse the Dershowitz position that (1) only statutorily defined crimes can amount to impeachable offenses and (2) “abuse of power” is by definition not impeachable.

“It does not make any difference at the end of the day, as Professor Dershowitz explained so well yesterday,” said Rep. Mike Johnson (R-La.), a member of Trump’s defense team. “Abuse of power and obstruction of Congress are not impeachable offenses, and it doesn’t really matter what anybody says.”

The rationale — goofy as it was — offered the Senate Republicans a possible way out of the vise the president had put them in by repeatedly insisting that his conduct was “perfect.” After the avalanche of evidence from House impeachment managers showing Trump did precisely what they accused him of, Trump partisans needed some way to sidestep the facts. For several of them, the “even if” argument that abuse of power and obstruction of Congress can’t give rise to impeachment seemed to do the trick.

That is, until Wednesday, when Dershowitz gave a stunning response to a question posed by Sen. Ted Cruz (R-Tex.).

In a slow, dramatic tone that left no doubt that he meant what he was saying, Dershowitz asserted that when a president “does 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.”

The derision from commentators and the legal community was near instantaneous. Dershowitz had embraced a position that is both self-evidently wrong and gravely dangerous. The parade of hypotheticals laying waste to it and showing that it sanctions presidential tyranny was inexorable. What about a president who promises a state election official a federal job in exchange for selectively suppressing his opponent’s votes? What about paying dirty tricksters to spread false information?

What about, for that matter, this very case, in which the president commandeered tax dollars for personal gain and invited the interference of a foreign country in the election?

In Dershowitz’s preposterous submission, all of these actions are immune from impeachment, since the president believes his reelection is in the public interest.

As the conflagration over his extreme overreach raged, Dershowitz, ever the fighter, simultaneously ripped into his critics and tried to settle back into his original submission, namely that impeachable offenses must be actual crimes, and abuse of power is not impeachable because "it is inconceivable that the framers would have intended so politically loaded and promiscuously deployed a term as ‘abuse of power’ to be weaponized as a tool of impeachment.”

But that position was itself untenable. On the first plank, Dershowitz himself acknowledged that his is a minority view, but that understates the case: Among credible scholars, there is really no serious view that impeachable offenses are limited to crimes, and the proof, which by now is well-worn, is multifarious and definitive.

His second argument, on “abuse of power,” is newer. The claim, which White House lawyer Patrick Philbin reiterated, is that the “abuse of power” standard is too amorphous to justify removal. It is just too easy to allege “abuse," and there always will be cases in which one senator’s abuse is another’s good government.

This reality, however, is nearly ubiquitous in the law. Most concepts in criminal law have gray areas. Was the action done “corruptly”? Was the confession “voluntary”? Was the risk “unreasonable”?

But that in no way shows that abuse of power cannot be an impeachable offense. On the contrary, it is the quintessential impeachable offense, and was uppermost in the Framers’ minds, after they experienced the erratic, abusive but not criminal conduct of mad King George. In the well-known words of Alexander Hamilton, “the subjects of its jurisdiction are those offenses which proceed from the misconduct of public men, or, in other words, from the abuse or violation of some public trust.”

Imagine a president who decides to play golf all day, every day. Or who insists on turning over all classified information to an adversary such as Russia.

Plainly, such a president would need to be removed. Yet under the Dershowitz view, the country would have no recourse.

Now that Dershowitz has fallen from favor with his self-inflicted wound, Republican senators hopefully will shy away from embracing his previous rationale, which while less incendiary is equally a prescription for tyranny.

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