President Trump thinks of himself as the victim of a “witch hunt” perpetrated by—depending on which day you check his Twitter account—12 or 14 or 16 “angry Democrats.”

In truth, Robert Mueller could have been much tougher on the president. And if he had been, everything might look different today.

First, suppose Mueller had issued a grand jury subpoena to the president early on.

Mueller explains in Part II and Appendix C of his report that he began his investigation by seeking a voluntary interview with Trump. After about a year, when the president was still declining to appear, Mueller agreed to accept written answers to questions instead. Those answers, Mueller acknowledges, proved to be almost useless—they were evasive, incomplete, and of course prepared by Trump’s lawyers. But by then, Mueller concluded that it was too late to begin an inevitably protracted litigation to enforce a grand jury subpoena. Mueller also thought that, even without the president’s testimony, he had sufficient evidence to determine the president’s intent for purposes of obstruction of justice.

Mueller could easily have made a different choice. Anyone who watched the nightly cable news implosions of Rudy Giuliani knew that he and his colleagues would never let their client voluntarily answer Mueller’s questions. For months, Giuliani went on television and professed his client’s desire to testify, while stating his own concerns about a potential “perjury trap.” It was all kabuki theater, of course; there was never a chance that Trump would actually talk to Mueller, and the only “perjury trap” his lawyers worried about was the prospect that Trump would get trapped in the process of committing perjury. Any sentient lawyer would have given a client like the president, with a reflexive instinct to lie, the same advice.

If Mueller had issued the president a grand jury subpoena early on, the president would, of course, have gone to court, but it is hard to imagine that it would have taken more than two full years to get the matter decided. And Mueller is likely to have prevailed. United States v. Nixon (the Watergate tapes case) and Clinton v. Jones (the Paula Jones case) strongly supported Mueller’s right to subpoena the president, and the principle that no person is above the law still has some resonance, at least in the federal courts.

Had Mueller secured Trump’s sworn testimony, things would surely have looked much different today. The president would have gone into a grand jury room, unaided by counsel, and would have had to answer questions posed by seasoned interrogators. No more open book tests. And if past is prologue, many of Trump’s answers would have turned out to be false. False testimony is, of course, a crime in its own right, but it also constitutes powerful evidence of intent with regard to the subject matter of the questioning. The president’s false testimony about the dozen or so episodes of obstruction detailed in the report would have provided evidence of intent for those episodes for which sufficient evidence was otherwise arguably lacking. And it would have greatly strengthened the inference of intent for those episodes where the proof was already sufficient.

Perhaps more important, false testimony from Trump would have made it more difficult for the president’s Amen Corner to proclaim his vindication once the Mueller Report was issued. This includes, most notably, Attorney General Bill Barr. Recall that in his surreal press conference just before the Mueller Report was released, Barr noted, as “weighing heavily” against any obstruction finding, that the president “fully cooperated with the special counsel’s investigation” and “took no act that in fact deprived the special counsel of the documents and witnesses necessary to complete his investigation.” That claim was misleading even at the time, but if Mueller had been able to point to actual perjury by the president, it is hard to believe that Barr—even Barr—could have invoked “full cooperation” as a reason for giving the president a pass.

Presidential perjury might also have affected the calculus in Congress. It would surely have stiffened the resolve of the wavering Democrats in the House and Senate for impeachment. And one hopes, perhaps foolishly so, that it might even have yielded some company for Rep. Justin Amash (R-MI) on the Republican side. At the very least, it would have been fun to watch the members of Congress who fulminated about President Clinton’s false testimony make excuses for President Trump’s answers to Mueller.

But suppose Mueller lost the battle to subpoena the president—what then? In my view, it still would have been worth the fight. For one thing, Trump would have had to give legal reasons for declining to testify. He couldn’t simply say, as he did in the absence of a subpoena, that his lawyers prevented him from testifying. Nor, as the Mueller Report discloses, could the president have decided for himself which questions he felt like answering. (Indeed, in view of the president’s stonewalling of Mueller’s questions, the special counsel would have been well within his rights to draw an adverse inference regarding Trump’s criminal intent).

Forcing the president to go to court would have required Trump to stake out a legal position. Presumably, the president would have claimed an immunity, based on separation of powers. Such an invocation, and the ensuing litigation, would have afforded the country a remarkable civics lesson, with countless reminders of President Nixon and other scoundrels who thought themselves above the law. If the president coupled his separation-of-powers claim with a Fifth Amendment invocation, at least some of his admirers—especially those prone to believe that only guilty people take the Fifth—might have been given pause. And although Mueller would have had to abandon the fallback option of getting written answers to questions, those answers, as Mueller himself has conceded, turned out to be nearly useless.

Second, suppose Mueller had made a formal recommendation on obstruction.

Mueller stated, both in his report and in his May 29 statement, that the Office of Legal Counsel opinion forbidding the indictment of a sitting president precluded him not only from charging Trump, but also from expressing a conclusion as to whether the president obstructed justice. Mueller perceived the OLC memo as a one-way ratchet: Although he was free to find against obstruction, he was forbidden to announce a determination that Trump had in fact obstructed justice.

Barr has called that judgment puzzling, and in this (limited) respect Barr is likely right. For one thing, nowhere in any of the pertinent opinions does OLC opine that prosecutors may not pronounce a view on the president’s wrongdoing. Indeed, as Mueller himself observed in his May 29 press statement, the 2000 memo expressly authorizes prosecutors to pursue criminal investigations of a sitting president throughout his term in office. Such investigations—as Trump’s daily tweet storms reflect—can be every bit as distracting and stigmatizing as a pronouncement that prosecution (or impeachment) is warranted. Yet OLC expressly anticipates that the investigations will go forward.

What is more, as Barr reminded us during his May 1, 2019, Senate testimony, Mueller’s report was a report to Barr . It was a prosecution memo. And the most basic task of prosecution memos is to offer a bottom-line recommendation on whether prosecution is warranted.

Mueller evidently thought it would just be unfair to announce a view on the merits when, by dint of the OLC memo, the president would not have the chance to defend those allegations in court. That is a noble enough instinct, but it is certainly not compelled by basic fairness principles. A sitting president who wants his day in court can simply jettison the OLC memo, risk indictment, and then make his case like any other citizen. Moreover, even without waiving the protections of the OLC memos, this particular president is skilled in the art of defending himself against opinions he doesn’t like. Indeed, he spent much of the two-year Mueller probe inoculating himself against adverse findings by demonizing the prosecutors and announcing his innocence of all possible charges. And if Trump thought he was wrongly maligned by an obstruction recommendation, he could always sue for defamation, a step he has taken in his private life more than once.

Having relinquished the duty to pronounce his own judgment, Mueller handed the hot potato to Barr, and the rest, as they say, is history.

Barr, of course, had auditioned for his current job by writing a memo contending that the entire suite of offenses identified by Mueller could never constitute obstruction, given the scope of the president’s Article II powers. Barr has also contended that the absence of an underlying offense—here, the failure to find that Trump conspired with the Russians in destabilizing the 2016 election—is an important reason to reject any obstruction charge. Not surprisingly, within 48 hours of receiving the 400-plus-page report and without reviewing any of the underlying evidence, Barr announced his opinion that the president was not guilty of obstruction.

Of course, the attorney general could have reached the same conclusion had Mueller made a contrary recommendation. But it would have been harder for Barr to do so, and more difficult for the president’s partisans to defend any such decision. By punting the question to Barr, Mueller allowed the president’s defenders to claim—with some plausibility—that Mueller could not decide the obstruction question (even though Volume II of the report reads like an indictment). And it allowed Barr to claim—admittedly, with less plausibility—that he had no choice but to decide the obstruction question himself. (In fact, the decision should be made—and presumably will be revisited—by whoever is AG when Trump leaves office and is no longer immune from indictment under the DOJ policy).

Finally, suppose Mueller now agrees to testify without regard to whether his answers go beyond the text of his report.

Bob Mueller clearly does not want to testify before Congress. In his May 29 press statement, Mueller advised Congress that, if it chooses to call him as a witness, he will decline to go beyond the four corners of his report.

Says who? Mueller is a witness like any other—you get asked a question, and you have to answer it. Sure, Mueller can try to confine his answers to what he has already said, but that tactic is apt to unravel, particularly if the questioners do a better job of preparing and coordinating than they usually do.

Indeed, Mueller’s May 29 press statement suggests that he has something important to add to his report. Notice, for example, that near the end of the statement Mueller made a point of commending the lawyers, investigators, and staff who worked with him on the investigation. To my ears anyway, this didn’t sound like boilerplate. It didn’t even seem like balm for the two years of vilification of the Mueller team by the president, by Trump TV, and by Trump’s auxiliary defense counsel in Congress.

Instead, it sounded to me as if Mueller understands full well the dangerous moment in which we find ourselves. The president—egged on by conservative media and a handful of folks who play lawyers on television—has now authorized the attorney general to embark on an investigation of the Mueller probe itself. He has even taken the reckless step of authorizing Barr to declassify any documents that may advance this probe. And Barr—whose conduct confirms that he is little more than Devin Nunes with better SAT scores and a receipt from Warby Parker—can be expected to release his findings just a few days before the 2020 election.

Bob Mueller cannot put a stop to this nonsense, but he could try. He could remind the public—in truth, inform the public, most of which will never read his report—exactly how the Russia probe began. How an actual participant in the Trump campaign somehow came to learn that the Russians possessed emails damaging to Hillary Clinton. How that revelation had nothing whatsoever to do with the Steele dossier, any “spies” in the Trump operation, or any of the other fever-dream allegations spun up on Fox News. Precisely because Mueller plays by the rules, his voice carries an authority that almost every other voice has lost.

Mueller’s institutional conservatism caused him to pull some punches during the Russia Investigation. If he now chooses to testify, and testify fully, some of the punches are likely to land.