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In 1838, Abraham Lincoln gave a speech on “the perpetuation of our political institutions“—better known today as the Lyceum Address. Dwelling on the threats facing the American political structure, he argued that the United States was protected from foreign invasion. “At what point, then,” Lincoln asked, “is the approach of danger to be expected?”

“I answer: If it ever reach us, it must spring up amongst us; it cannot come from abroad. If destruction be our lot, we must ourselves be its author and finisher. As a nation of freemen, we must live through all time, or die by suicide.”

The description of the United States as a “nation of freemen” three decades before emancipation was a bit of a stretch. But there is wisdom in Lincoln’s warning. It has been on my mind lately, as the country debates the question of impeachment in the wake of Special Counsel Robert Mueller’s report.

Here are the facts: The president is unsuited to his office. That should have been obvious well before the release of the special counsel’s report, but the text of the report, even with a smattering of redactions, makes his unfitness brutally clear. He shows no understanding of the responsibilities of the presidency. He delights in the abuse of his power. As Memorial Day approaches, he is reportedly planning to celebrate the holiday by pardoning, among other service members accused of war crimes, a Navy SEAL scheduled to stand trial for the murder of multiple unarmed Iraqi civilians.

To respond appropriately to Donald Trump’s behavior is to risk appearing absurd, because his own conduct is so extreme that any proportionate reaction could be deemed an overreaction. The industry of anti–anti-Trumpism is devoted to describing opposition to the president as hysterical—but an emotional excess of anger and sadness is exactly what this excessive presidency merits. What this means, in part, is that reaction to the president muted by circumstance or a desire to appear “reasonable” will always be insufficient. The only adequate response to Trump is the cry of protest. But every protest ends, even as the outrages that provoked it persist.

There is a constitutional mechanism for sounding that outrage in a more enduring way. It’s the impeachment process.

Speaker of the House Nancy Pelosi remains firmly opposed to beginning impeachment proceedings, even as multiple Democratic members of the House Judiciary Committee have called for the start of an inquiry and one Republican, Representative Justin Amash, has outright declared that the president should be impeached. Pelosi’s argument appears to be that there is no need to begin this process; that Democrats can obtain information through litigation without resorting to an impeachment inquiry; and that such an inquiry risks shoring up support for Trump as the country heads toward the next presidential election.

This is a very practical argument. But there is value to an impeachment inquiry—and to impeachment—as an act in itself, regardless of whether the Senate will convict or what the president’s supporters will think.

Pelosi and the more hardheaded Democratic strategists regard this position as overly idealistic. That’s the point.

I have returned again and again in recent weeks not just to the Lyceum Address, but also to Albert Camus’ The Rebel—the philosopher’s attempt to grapple with what it means to live morally in an absurd world. For Camus, the foundational human experience is one of outrage: a “fruitless struggle with facts,” an “incoherent pronouncement” of pain and frustration with injustice.

Camus’ reasoning can apply to an almost endless range of situations, from frustration with a corrupt political regime to rage at the inevitability of death and the silence of God. Much is absurd about the Trump administration in a colloquial sense: Consider the spectacle of a tweeting commander in chief, the most powerful man in the world spending his time insisting on falsehoods and sniping over obvious insults. But his presidency is also absurd in the philosophical sense. What better to emphasize the gap between the desire for the Constitution to mean something and the reality of the document as some words on paper than the scene of Donald J. Trump swearing an oath to “faithfully execute the Office of President of the United States, and … preserve, protect and defend the Constitution”?

The Constitution is what Camus would call a “closed universe”—a space of “coherence and unity” in an incoherent world, in which words carry weight and actions have consequences. Trump’s disrespect for the law is a reminder of how fragile that structure of meaning can be. For that reason, there is a real service in using impeachment proceedings to push back against the notion that, in the parlance of the internet, “lol nothing matters.”

Susan Hennessey and I have argued that the House of Representatives has a duty to begin an impeachment inquiry insofar as representatives swear an oath to “support and defend the Constitution” and to “well and faithfully” execute the duties of their office. Another way of saying this is that an impeachment inquiry depends on an insistence that this oath really means something—and that the president’s oath means something as well. Keith Whittington, likewise, has written that impeachment is partially a matter of “norm creation and norm reinforcement.” And Yoni Appelbaum argued that the impeachment of Andrew Johnson “drew the United States closer to living up to its ideals.”

Gerald Ford, as a member of the House of Representatives, argued in 1970 that an impeachable offense is “whatever a majority of the House of Representatives considers it to be at a given moment in history.” He was not wrong that impeachment is a political process; it is, after all, entrusted to Congress. To treat the subject as an entirely political calculation, though—as Ford did and as Pelosi appears to be doing now—is to slouch toward nihilism. Treating the words high crimes and misdemeanors as if they hold real significance, however, is a way of protesting that the world should not be as it inevitably is.

This is perhaps overly earnest. But there is a real humanity and purity of purpose in asserting earnestness against the void.

The House should take up the task of examining the president’s conduct as detailed in the Mueller report and evaluating whether it is fitting of the person who holds the nation’s highest office. It should investigate the many other instances of potentially impeachable conduct by the president, from tweets to pardons. It should debate how to understand what constitutes a “high crime and misdemeanor,” and whether relatively minor offenses can accumulate over time into something worthy of impeachment. The House should fulfill its constitutional duties and the process of constitutional interpretation, which by its nature is a declaration that the Constitution holds some significance.

Lincoln’s warning of the “approach of danger,” in context, was less about the political fracturing that would lead to the Civil War and more about the creeping acceptance of what should have been unacceptable. He decried “the increasing disregard for law which pervades the country; the growing disposition to substitute the wild and furious passions in lieu of the sober judgment of courts; and the worse than savage mobs for the executive ministers of justice.” It was this, in his mind, that pointed toward the death of the nation. The antidote he offered was “the support of the Constitution and laws.” In the absence of that, the cynical country would become vulnerable to the approach of a dictator: “Distinction will be his paramount object … and nothing left to be done in the way of building up, he would set boldly to the task of pulling down.”

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