The President has now spoken on the subject of the appointment of a special counsel for the Russia investigation. This morning, he communicated on Twitter to express his unhappiness. He said the probe is a “witch hunt.” He is convinced that the system is biased against him, probing charges that he believes to be without foundation while ignoring illegal acts committed in prior Democratic administrations. The reporting of this Twitter commentary has followed the usual pattern of noting the absence of facts for the assertions that Trump made. But the absence of an evidentiary basis for these tweets is not what makes them significant.

There is indeed a fact reflected these tweets: the President’s ongoing resistance to this probe and his attack on its legitimacy. This is his position: that it is a "witch hunt." The President is declaring in unmistakable terms his rejection of special counsel Robert Mueller's investigative mission. Later in the day, he called it a “very, very negative thing,” and “terrible” for the nation. In his East Room press conference with the President of Colombia, he somewhat tempered his remarks and his tone, perhaps adjusting his comments to the setting of a formal joint event with the leader of another nation. It was not the best forum for his core message about the investigation. Still he did not fail to repeat that he was the victim of a “witch hunt.”

It is important to note that the President is making three distinguishable but related claims: (1) that the probe is being conducted for no legitimate reason; (2) that it is being directed against him as a particular political target, by his political enemies; and (3) that the discriminatory character of this investigative attack is underscored by the absence of anything like it in prior administrations when clearly illegal acts took place without consequence.

There are multiple audiences for these communications. There are his allies who seem to be falling in step with him in making the accusation that the "deep state" is engaged in a politically motivated manipulation of the criminal justice process. With his comments today, the President is certainly urging them on. Then there is the audience in the wider public, in his “base” in particular, whom he is working to keep in his corner. His message to them is that the process is illegitimate: It is more proof of what he had said all along was the implacable hostility of the Establishment to the outcome of the election and his determination to shake things up in Washington. And through this base the President is disseminating this message to the Capitol Hill Republicans whose loyalty has been tested and whom he must remind of the political support he still commands—if he can hold on to it.

This is not simply politics. Knowing or half-knowingly, the President may be putting in place the elements of a strategic response to this investigation and any prosecutions that may result.

The first and most obvious of these moves is laying the foundation for moving against the investigation at some point in the future, if and whenever he should decide it is necessary to do so.

The President certainly has the authority to stop this investigation in its tracks. He may have no intention of doing so now; he may never do so. If, however, the President wishes to retain the flexibility to disavow it later, and bring it to a close, he might have decided to preview the grounds for this action. Over the next several months, he may be presented with the opportunity to build on his conviction, or at least his claim, that he is being systematically mistreated for reasons having to do only with corrupt politics, not with legitimate law enforcement.

It is a mistake to assume that every president following Nixon would conclude from the Saturday Night Massacre that someone in Mr. Mueller's position could not be fired, or the investigation ordered to close down. But Nixon and Trump are not the same; the times are not the same. Nixon raged against the establishment but craved an acceptance it would not give him. He was, after all, more Establishment than not: years of public service in the Congress and as Vice President, and time in law practice with a prestigious New York firm. Trump similarly hungers for approval but if conventional honors or accolades are denied to him, he seems willing take his recognition and support where he can get it. In the end, Nixon would not burn the tapes. In the same situation, what would Donald Trump do, if bolstered by the support of those who subscribe to his narrative of victimization?

That Trump may be instinctively keeping open the case for ending the investigation (or replacing the ones in charge of it) does not mean that, considered objectively, it is a plausible strategy. He would likely have to fire multiple officials. Nixon had to endure two senior-level resignations before Robert Bork would execute the order to dismiss Archibald Cox. The outcry would be fierce. The Congress would respond, and that response would include movement toward a serious impeachment inquiry. It cannot be known how the President judges the likely consequences of some future interference in this investigation, and he may not now be looking that far ahead. It is known that the president’s judgments differ materially from those of others, as evidenced by his failure to foresee the reaction to the firing of Mr. Comey—a failure that included the mistaken belief that Democrats would applaud the move.

The course of active resistance is available to Trump in the fractured and polarized media environment different from the one with which Nixon contended. He can communicate directly with his supporters and he can find outlets for supportive editorial and other commentaries. Perhaps it does not go on forever: events may catch up to him, particularly if the economy slows down or his supporters lose confidence in his confidence. So far, he appears to be hanging on. And this may be support enough for him to keep alive the option of following up his attack on the investigation with formal action to destroy it.

The public denunciation of the appointment of the Special Counsel may also have some intended effect on the individuals swept up in this investigation as witnesses. Are the tweets a dog whistle, sounding the alarm that this is no normal investigation and rousing to resistance anyone within his self-described movement? Certainly they are not hearing a presidential call for support for this inquiry and a pledge of cooperation. Now if this is part of the plan, it may be doomed to fail. Those who face criminal prosecution make decisions in their own interests, and their lawyers certainly counsel them accordingly. It can hardly escape attention, however, that the President of the United States has declared that Mr. Mueller is leading a "witch hunt."

Then there is question of how, in another way, this may affect Robert Mueller’s investigation. Mueller is careful, the consummate professional. Anyone familiar with his career would expect that he would apply the law with rigor to a meticulously developed factual record. Now, however, he and his team understand that the President has attributed to them complicity in a politically motivated investigation—one that is "terrible" for the country. Mr. Mueller must know that, if he survives in this position, he can count on a furious counterattack on any prosecution that results from this investigation. This will not be the reason why Mueller will be methodical and thorough in the conduct of the investigation and eventually in the exercise of his prosecutorial discretion. But it will give him added motivation to get this right—and he will have every incentive to take his time to get it right. This last result—more, not less time, needed for the probe—is probably a potential result of his comments that the President did not fully think through.

These are additional reasons why the "Watergate" analogy only goes so far, and it may be more misleading than illuminating. What we're seeing now is not better or worse than Watergate, or the same. It's very different: We have not seen anything like it before. In the next days, the choice of FBI Director may give further clues to how Mr. Trump is preparing to defend himself against this “witch hunt.”