From the day that Donald Trump was inaugurated as president, people have been arguing that he should be impeached. That effort faced some rather serious obstacles. Not everyone was convinced that any impeachable offenses had been committed. Not everyone was convinced that impeachment was the right remedy, even if the president had committed impeachable offenses. Perhaps most importantly, the president’s party won majority control of the House of Representatives in 2016, and Republicans had little interest in impeaching their own president.

That calculus has changed in recent months—but only somewhat. The release of the Mueller report has clarified whatever impeachable offenses might exist as a consequence of the Trump campaign’s actions before the 2016 election and of President Trump’s actions during the investigation of Russian interference with that election. For those who said that impeachment inquiries should wait until the special counsel had concluded his investigation, the wait is over. For some, that report has strengthened the case for impeachment. For others, it has weakened the case. Republicans certainly have not been convinced—but their opinion matters less, as they lost control of the House in the 2018 midterm elections.

Now with a majority in the House, the Democrats hold the power to impeach the president entirely in their own hands. What they do not have is the power to convict and remove the president from office. To do that, they would need to swing some Republican votes in a Senate trial, and at least for the moment that seems like a bit of a longshot. The Democratic members of Congress might well feel compelled by their base to move forward with an impeachment even if the prospects of a conviction in the Senate seem slim, but they should at least understand what, if anything, they might be accomplishing by doing so.

Ordinarily, it would not make sense to impeach an officer if acquittal in the Senate is a foregone conclusion. The most obvious reason to impeach someone is because there is an urgent need to remove him or her from power. If conviction is off the table, then removal can no longer be the justification for moving forward with an impeachment. Justice Joseph Story thought it a “vain exercise” to move ahead with an impeachment after an officer had resigned from his position in government precisely because “the most important object, for which the remedy was given, was no longer necessary, or attainable” in such circumstances.

There might well be some reasons to impeach even when conviction at trial is unlikely. To begin with, there could be political rewards to be reaped from a doomed impeachment effort. Some party donors and activists might be energized by an impeachment and rally to those members of Congress who showed their willingness to fight the good fight. Perhaps some members of Congress would feel a moral obligation to impeach if confronted with sufficient evidence of sufficiently serious misconduct by high government officials. Perhaps the exercise of an extended and public impeachment inquiry in the House will shift public and political perceptions of the case against the president where two years of media coverage and legal investigations have not. I will leave such considerations to the side and refrain from attempting to assess how grave the sins of Trump might be.

Are there pragmatic but specifically constitutional reasons to pursue a seemingly futile impeachment? Sometimes there are—and advocates of impeachment by the House would be well advised to tailor their arguments toward constructing a justification for impeachment that would stand even if conviction and removal were not likely to follow. Pursuing a presidential impeachment for the wrong reasons can itself be damaging to the political system.

Focusing on the fate of an individual officeholder risks missing the point of impeachments that do not lead to conviction and removal. If the entire purpose of impeachment is to remove Trump from office, and he remains in office after the attempt, then the impeachment has obviously failed. If the goal is to stop a string of abusive behavior that can no longer be tolerated or checked by other means, then an impeachment that ends with the abusive official still in office has failed. If the goal is to address a basic incompatibility between the behavior of an officeholder and the expectations of the office, and that incompatibility remains at the end of the process, then the impeachment has failed. If the goal of an impeachment is to stop an officeholder from continuing to exploit his or her governmental office for personal gain, and the officer continues to be able to aggrandize him- or herself at the public expense, then the impeachment has failed.

On the other hand, if the point of an impeachment effort is less to remove a particular individual from office than to establish or reinforce the proper expectations of officeholding, then the ultimate fate of the impeached officer is of less importance than the message sent by the impeachment. Impeachments can be, and have been, a vehicle for constructing, consolidating and reinforcing an important set of constitutional norms. They are a means for asserting that some behavior is beyond the pale. An impeachment can send the strongest possible message that some behavior is to be condemned and should not be imitated by others—that even though a high government official has engaged in some behavior, this behavior should be understood as disgraceful rather than exemplary.

Norm creation and norm reinforcement have long been part of the American experience with the impeachment power, particularly when the House set its sights on the highest government officials. The Jeffersonians impeached Associate Justice Samuel Chase so that judges would understand in no uncertain terms that political partisanship should have no place on the federal bench. Chase had distinguished himself for the partisan enmity with which he held the Jeffersonians, and his impeachment helped recalibrate expectations about how life-tenured judges should behave in a democratic but partisan political environment. Decades later, the Republicans impeached President Andrew Johnson because he was engaged in an unprecedented obstruction effort that relied on an expansive view of presidential authority in the high-stakes context of the aftermath of a civil war and in the midst of Southern reconstruction.

Both Chase and Johnson were impeached by the House but acquitted in the Senate. Partisans of both officials spun the House’s failures to win a conviction as evidence that the House had itself engaged in partisan overreach and abused its constitutional prerogative. But in both cases, political elites got the message and refrained from following the lead of Chase or Johnson. Twentieth-century advocates of presidential power, for example, look back on the Johnson impeachment as outrageous because Johnson’s use of presidential powers seemed so consistent with modern practices and expectations. (It should be noted that the critics of Reconstruction also had a thing or two to say about how misguided the Republicans were to pursue the Johnson impeachment.) If Johnson was ahead of his time, however, his contemporaries saw him in a different light. They wanted the kind of congressional government that characterized the late 19th century but that would later become anathema to advocates of modern presidential power in the 20th century. Johnson’s impeachment was part of the Republicans’ effort to construct the kind of constitutional order that they wanted, and in that they succeeded (at least for a couple of generations)—even if they allowed Johnson to serve out his term so long as he promised to cease his obstructionism.

That said, there are risks involved in using the impeachment power as a tool for supporting constitutional norms. An impeachment might divide the country rather than unify it around those norms and, as a consequence, might leave norms in a weaker state than they otherwise would be. The overall message of an impeachment might be misread if the Senate refuses to convict, leaving friends of the impeached officer to argue that the target of the impeachment was in fact vindicated by the Senate’s action. An impeachment is a high-stakes confrontation, and advocates of impeachment should consider the consequences of losing as well as the potential benefits of winning. If the goal of an impeachment is to bolster constitutional norms, then the fight over the legacy of the impeachment will be as important as the battle over the impeachment itself.

It is always worth considering whether alternative tools can accomplish the desired goals just as well or better than the tool of impeachment. If the goal is to bolster political norms, then a resolution of censure or even simple electoral victory might be equally or more effective in conveying to other ambitious political operatives that a particular officer’s example is not one worth following. It is possible to cheapen the coin of impeachment by spending it too often and too meanly. If an impeachment is come to be seen as mere partisan showboating, then it will be worse than useless. Officers must fear impeachments as politically costly and reputationally damaging, even if they are survivable.

An impeachment that only seems to redound to the political benefit of the impeached official is more likely to subvert norms than reinforce them, and more likely to embolden norm breakers than chastise them. Impeachment campaigns may be moments of high drama, but the protagonists must take care not to unwittingly cast themselves in the role of the villain rather than the hero. Being clear about why an impeachment should be pursued, and what it should be understood to mean, is essential to convey the right moral of the story.