Another option is to smear not just the whistle-blower, but all those other witnesses as well. Indeed, this weekend Trump hinted vaguely at information the press will learn “very soon” about Vindman’s political affiliation. But the unexpected Republican revolt against the suggestion of Vindman having dual loyalties suggests that, at this late hour of the day, there may finally be some defenses that just will not fly.

Then there’s the option of falling back on process complaints. During the vote on impeachment procedures, House Minority Whip Steve Scalise foreshadowed this approach, standing in front of a large placard with an image of a hammer and sickle alongside St. Basil’s Cathedral and decrying the “Soviet-style,” “sham” impeachment process that he understood the resolution would authorize. Meanwhile, House Minority Leader Kevin McCarthy argued to reporters that the investigation had been poisoned from the outset by a lack of “due process” and that a vote midway through could not undo that damage. In McCarthy’s description, the Democrats’ initial decision to hold closed hearings is a poisonous tree, and all subsequent impeachment processes are its malign fruit.

The problem with this approach is that it assumes people will be so outraged by closed-door depositions weeks earlier that they will not care or hear what live witnesses are saying in public in real time. Process arguments, particularly bad ones, can get the president only so far.

The final option is to cease contesting what happened, but to assert instead that it was the president’s prerogative to act as he did, that he acted properly or reasonably, or at least that—whatever one may think of his choices—he did not act impeachably. The Washington Post the other day reported that Senate Republicans were heading in this direction. And this defense, from a strategic point of view, is well advised. It is, after all, the only option that doesn’t require the denial of facts, the defamation of individuals, or persistent distraction from what the president actually did.

But this approach will require a redefinition of long-standing public perceptions of presidential propriety, to claim that nothing is unacceptable about a president using the tools of statecraft for individual gain. According to the Post, this would likely make more moderate Republicans edgy. What’s more, this tactic has already been tried once—by Acting White House Chief of Staff Mick Mulvaney, who angrily insisted that anyone outraged by the quid pro quo should just “deal with it.” And it quickly backfired, with Mulvaney forced to retract his statement.

As the public phase of impeachment proceedings begins in our era of perfect partisanship, has the expectation that presidents will act in a public-spirited matter now also become a partisan stance?