Andrew Harnik / AP

On February 27, 1860, Abraham Lincoln stood before a simple wooden lectern in New York City’s Cooper Union and delivered one of the most consequential speeches of his life. He offered a ringing condemnation of slavery, an unapologetic appeal to the righteous position of the free states, and a clear-eyed assessment of the dark and dangerous years ahead.

When the tall prairie lawyer began this speech, he was to many little more than a failed candidate for the U.S. Senate. By the end of his 56-minute oration before New York’s GOP grandees, Lincoln was on track to win the 1860 Republican presidential nomination.

For Lincoln, and the Republican Party of his day, there was no moral compromise to be sought or attained on slavery. It was wrong. It was evil. It was un-American. By the acts and deeds of the Founding Fathers, the federal government had the authority to, at the very least, forbid the spread of involuntary servitude, whether the South liked it or not. Lincoln sought not to mollify the South or to compromise with the culture of slaveholding, but to draw a clear line.

Today, the United States faces a different threat, and as in Lincoln’s day, it is a threat not from abroad, but from within. The Republican Party, which some of us still hope to reform and which others have left, no longer deals in principle, morality, or the pursuit of the common welfare. It is no longer a party driven by a commitment to the rule of law, the preservation of individual liberty, or adherence to the Constitution.

The GOP now exists to further the personal desires and wealth of one man. We now see friends and former colleagues celebrate its new form. It is no longer a party of ideas, but a party of idolaters. It is a dark mirror of the authoritarian regimes we once fought.

In the past several decades, America has experienced a steady dilution of the power, competence, and value of our institutions, and the near collapse of what we once called political discourse. Public trust in government, business, religious institutions, and our faith in the idea of America is strained to the breaking point. As Lincoln understood on the eve of the Civil War, we need a clarion call to hold the line against a tyranny from within.

If Donald Trump wins a second term, the consequences will be dark—and it does no one any good to deny them. The month following his Senate acquittal has given us a preview of what lies ahead. Even his friends and fans now understand what Trump might do with untrammeled power in a second term.

Since taking office, this president, despite his radical, reckless, and corrupt actions, his constant stream of unpresidential words and deeds, has faced no substantive sanction, official or otherwise. A reelection will embolden him and his allies in ways Americans should fear.

Much of America feels helpless to confront a president who treats the rule of law as a joke, who weaponizes the federal government against his political and personal opponents, and who engages in corrupt acts for his personal benefit.

That is why in December of last year, we founded the Lincoln Project. Like the president whose name we have humbly adopted, we know that to “bind up the wounds” of our Republic, we must first defeat the most clear and present danger to it.

However, while defeating Trump at the ballot box in November is our primary stated goal, our mission in the end is not merely about him. Those who claim we are “Never Trumpers” are missing the broader scope of history. Lincoln wasn’t just “Never Slavery”; he was “Always America.” He fought slavery’s horror, risking the end of the Republic in order to save it.

Trump is the antithesis of what the Republican Party was founded to defend, and that makes him the tangible and temporal target of our current efforts. Defeating him is only the beginning of a national reformation that will be the work of years, perhaps decades.

We come to this fight believing that our country is bigger than any one person or faction, and that the roaring tribalism of the right and left is a dead end for what should be a nation of unlimited promise. We love America, and what it stands for, not because of some ideological predisposition, but because it has created a place where liberty and freedom aren’t brand slogans, but sacred truths.

We are not pro- or anti-Republican or pro- or anti-Democrat. We are pro-liberty, pro-institution, and pro-Constitution. We are small-l liberals and small-c conservatives, militant optimists, and believers in the American experiment. We love this nation for all its flaws and all its wonders. We know our collective potential as a nation but are not blind to our collective shortcomings.

Donald Trump is not, in our vision, the worst potential outcome. But he has claimed the mantle of “law and order” for only himself and his allies. For all others who would enjoy the liberties and protections of the United States Constitution, the “rule of law” is no more than a faded and peeling bumper sticker.

He has run roughshod over the traditions and institutions that are supposed to allow Americans—all Americans—the freedom to do what they believe is right for themselves, their families, and their communities, without the fear and uncertainty that strongmen and zealots create.

He is, for now, the most powerful exponent of a political system in dire need of wresting away from those who would utilize its levers for their own purposes, who would leave America weaker, and who would certainly leave individual citizens worse off for their trouble.

Donald Trump’s supporters showed a level of strength and unity that took us by surprise. There are many reasons for that, and many other places to find explanations. Unfortunately, their strength has unleashed forces long constrained both by institutions and by traditions. Those bulwarks of liberty lie broken and breached. This may give the president’s supporters momentary joy. Left unchecked, it presages a darker future for our country and our children.

Lincoln’s Cooper Union address offered not only a master class in research, logic, and rhetoric, but also an example of moral clarity. He refused to be dissuaded by invective, or threats of physical violence. He refused to allow slavery’s supporters to employ “contrivances such as groping for some middle ground between the right and the wrong.”

He knew the war was coming. He also knew the importance of making the clear moral case, even against terrible odds.

Lincoln’s determination would be tested again and again in the campaign that followed, and during his presidency. He would lead this nation in its darkest hours, when the Confederate army was a day’s march from Washington and when the pressures for compromise, settlement, and accommodation rose along with the death toll of the Civil War. He never bent, never broke, and never took the easy path. He paid the ultimate price to preserve this Union.

As Lincoln said in 1860, there is no middle ground when it comes to right and wrong. We cannot and will not stay on the sidelines as amorality becomes the order of the day in our country and our politics. We take on this president, in this time, because we know that a better and brighter future awaits when he is gone.

Trump is symptomatic of our more intractable problems, but he is a symptom that, unaddressed and unexcised, may damage the body politic beyond repair. Just as Lincoln recognized the storm clouds massing ahead of the Civil War, we see clearly the gravity of our mission and the enormous tasks before us.

Lincoln concluded his Cooper Union speech in words that need no embellishment: “Neither let us be slandered from our duty by false accusations against us, nor frightened from it by menaces of destruction to the Government nor of dungeons to ourselves. Let us have faith that right makes might, and in that faith, let us, to the end, dare to do our duty as we understand it.”

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