Opinion | There Are Four Anti-Trump Pathways We Failed to Take. There Is a Fifth.

Democratic self-rule contains a paradox. It is a system premised on openness and competition. Any ambitious party or politician should have a shot at running for office and winning. But what if a major candidate seeks to dismantle that very system?

America confronts this problem today. Donald Trump poses a clear threat to American democracy. He was the first president in U.S. history to refuse to accept defeat, and he illegally attempted to overturn the results of the 2020 election. Now, on the brink of returning to the White House, Mr. Trump is forthrightly telling Americans that if he wins, he plans to bend, if not break, our democracy.

Mr. Trump tells us he plans to prosecute his political rivals, including Joe Biden, Kamala Harris, Liz Cheney and other members of the Jan. 6 Select Committee; deploy the army to repress protest; and order the deportation of 15 to 20 million people, including some legal immigrants.

We have been studying democratic crisis and authoritarianism for 30 years. Between the two of us, we have written five books on those subjects. We can think of few major national candidates for office in any democracy since World War II who have been this openly authoritarian.

The view that Mr. Trump poses a grave threat to democracy is shared by his former chairman of the Joint Chiefs of Staff, Gen. Mark Milley, who called him “fascist to the core,” and by his former chief of staff, retired Marine Gen. John Kelly, who described him as a fascist who prefers dictatorship to democracy.

How could such an openly authoritarian figure have a coin flip’s chance of returning to the presidency? Why have so many of our democracy’s defenses seemingly broken down, and which, if any, remain?

We spent the last year researching how democracies can protect themselves from authoritarian threats from within. We have found five strategies that pro-democratic forces around the world have employed. None offer foolproof protection (no democracy could enjoy foolproof protection and remain a democracy), and some of them come with important drawbacks. But our research suggests that in the face of imminent extremist threats, these strategies are the best available.

The traditional American response to extremism is laissez-faire which makes it almost odd to call it a strategy. We rely on the self-correcting power of electoral competition. The belief is that all opinions should compete freely, allowing the marketplace of ideas, or what John Stuart Mill called “the collision of adverse opinions,” to play out. If we let all candidates compete, the thinking goes, good ideas and candidates will ultimately beat out the bad ones.

Electoral competition is, of course, essential to democracy. But a laissez-faire approach has two important limitations. First, in the United States, competition is distorted by an 18th-century institution, the Electoral College, that allows election losers to win power. In one sense, the electoral marketplace worked in 2016 the way it is theoretically supposed to: More Americans voted for Hillary Clinton than for Mr. Trump. But the Electoral College permitted an authoritarian figure who won fewer votes to become president.

In addition, history shows us that electoral competition alone is insufficient to fend off extremist threats. Good ideas don’t always win out. And candidates seeking to subvert democracy don’t always lose. In the past quarter-century alone, leaders like Hugo Chávez in Venezuela, Viktor Orban in Hungary, Kais Saied in Tunisia and Nayib Bukele in El Salvador have won decisive electoral majorities — and then used their elected offices to undermine fair competition, making it nearly impossible to remove them from office democratically.

Yet democracies are not helpless. There are four other strategies for fending off authoritarian threats from within. One of these is a far more muscular approach, known as militant or defensive democracy. Born in West Germany as a response to Europe’s democratic failures in the 1930s, the militant democracy approach empowers public authorities to wield the rule of law against antidemocratic forces. Haunted by the experience of Hitler’s rise to power via the ballot box, West German constitutional designers created legal and administrative procedures that allowed the state to restrict and even outlaw “anti-constitutional” speech, groups and parties. In the 1950s, these tools were used to ban both a Nazi successor party and the Communist Party. Today, German authorities are investigating the far-right Alternative for Germany, or AfD.

Obviously, there are significant drawbacks and risks to empowering public officials to bar candidates or parties from elections. Candidate disqualification distorts electoral competition and restricts voter choice. Worse, the tools of militant democracy are easily abused by politicians seeking to sideline their rivals, as has occurred with some frequency in Latin America.

Nevertheless, most contemporary democracies employ elements of militant democracy. In South Korea, the Constitutional Court banned the Unified Progressive Party in 2014 because it deemed the party’s pro-North Korean views to be antidemocratic. In Brazil, the Supreme Electoral Court has the authority to bar politicians convicted of corruption and other crimes from running for office, and a 2021 democracy protection law made it a crime — punishable by up to 12 years in prison — to attempt to overthrow a democratic government. Last year, a former president, Jair Bolsonaro, who, like Mr. Trump, tried to discredit and then overturn an election, was barred from public office for eight years.

The United States has a tool on the books for disqualifying anti-constitutional candidates: Section III of the 14th Amendment disallows former public officials who have “engaged in insurrection or rebellion” from holding office. Intended to bar Confederate leaders from public office, Section III might have been used to disqualify Mr. Trump from the ballot — as Colorado’s Supreme Court ruled in late 2023 with regard to its state’s primary ballot. Earlier this year, however, the U.S. Supreme Court ruled that, barring congressional legislation, the 14th Amendment could not be used to keep Mr. Trump off the ballot. With that decision, for good or ill, America chose to forgo the path of militant democracy.

A third approach to defending democracy is partisan gatekeeping. In the absence of legal tools to block extremist threats, the responsibility for fending off such threats falls to political parties. In a healthy democracy, party leaders police their own ranks, expelling antidemocratic elements or refusing to nominate extremists or demagogues for public office.

American parties were effective gatekeepers throughout the 20th century. In the early 1920s, Henry Ford, the plain-spoken founder of Ford Motor Company, who was admired by many Americans but whose extremism and anti-Semitism was embraced by Hitler and the Nazis, considered running for president as a Democrat. Early polls showed him leading the pack of potential candidates. But Democratic leaders never seriously considered him. Finding the party’s gates closed, Ford abandoned his presidential aspirations.

Half a century ago, Republican leaders engaged in self-policing when they joined in congressional investigations into wrongdoing by President Richard Nixon. When Mr. Nixon’s abuse of power was brought to light, key Republican leaders supported impeachment. Their actions shifted public opinion in important ways. It was not until a group of Republican lawmakers came out in favor of impeachment beginning in late July 1974 that a clear majority of Americans supported Mr. Nixon’s removal from office.

Today’s Republican leaders have abandoned gatekeeping. Even after Mr. Trump tried to overturn the 2020 election, they protected and supported him. Had Senate Republicans voted to convict and disqualify Mr. Trump after his second impeachment, he would not be a candidate today. But they did not. And now, nearly all Republican officeholders support Mr. Trump’s presidential candidacy, despite having witnessed, firsthand, his assault on democracy and the rule of law. Captive to an authoritarian outsider whom they should have kept out, Republican leaders now imperil, rather than defend, democracy.

When authoritarians make it onto the ballot, prodemocratic forces may turn to a fourth strategy: containment, in which politicians from across the ideological spectrum forge a broad coalition to isolate and defeat the authoritarians. Building a multiparty coalition requires that politicians temporarily set aside many of their short-term ambitions and policy goals. Such sacrifice is arguably in their long-term interest, because without democratic institutions, politicians’ ability to pursue their short-term ambitions and policy goals will be undermined.

Opposition parties engaged in successful containment last year in Poland. When the illiberal Law and Justice Party government sought a third term, Poland’s fragmented and ideologically diverse opposition united to defeat it. The center-right Civic Platform of the former prime minister, Donald Tusk, built an alliance with former communists, greens, the conservative Peasant Party and a party led by Szymon Holownia, a television personality and presidential aspirant, to confront Law and Justice in the October 2023 parliamentary elections. The parties negotiated unified tickets — to avoid splitting the vote — for Senate races and, after jointly capturing a majority of seats in the election, elected a new government, putting an end to nearly a decade of democratic backsliding.

On several occasions, French parties have contained illiberal forces by forging what they call a cordon sanitaire — a multiparty electoral coalition aimed at isolating and defeating far-right extremists. That strategy proved strikingly successful in July, when Marine Le Pen’s radical right National Rally stood poised to become the largest force in Parliament after the first round of legislative elections.

In the face of an imminent far-right victory, party leaders and activists from across the spectrum, including the communists, greens, socialists, centrists and center-right Republicans, worked together, district by district, to persuade allied candidates to stand down and back a single candidacy against Ms. Le Pen’s forces. Notwithstanding considerable acrimony among the parties, the strategy succeeded: The united “republican front” relegated the National Rally to third place.

In the United States, some Republican politicians have embraced a containment strategy. In a textbook example, the former Representatives Liz Cheney and Adam Kinzinger, both Republicans, cooperated with Democrats on the House Jan. 6 Committee. Ms. Cheney, Mr. Kinzinger, former Vice President Dick Cheney, and a handful of other prominent Republicans took the important step of supporting Kamala Harris for president, making it clear that the threat posed by Mr. Trump outweighed any partisan loyalties or policy preferences.

But containment is hard in a polarized two-party system. Most of the prominent Republicans who have not endorsed Mr. Trump, including Senator Mitt Romney, former Vice President Mike Pence, and former President George W. Bush, declined to back Ms. Harris, opting instead to remain on the sidelines. Other leading Republicans who declared Mr. Trump unfit for office after 2020, such as Senator Mitch McConnell, the minority leader, and Nikki Haley, a former South Carolina governor and U.N. ambassador, who ran against Mr. Trump this year, now support him. As long as Republican leaders who privately view Mr. Trump as a grave danger refuse to go public, most Republicans voters will remain unmoved.

That leaves a fifth strategy: societal mobilization. Democracy’s last bastion of defense is civil society. When the constitutional order is under threat, influential groups and societal leaders — chief executives, religious leaders, labor leaders and prominent retired public officials — must speak out, reminding citizens of the red lines that democratic societies must never cross. And when politicians cross those red lines, society’s most prominent voices must publicly and forcefully repudiate them.

A recent example of societal mobilization is the German public reaction to the revelation of a secret November 2023 gathering in which leaders of the far-right AfD met with neo-Nazi groups and discussed a plan for the mass deportation of immigrants, including foreign-born German citizens.

When the meeting came to light, the chairmen of the boards of Mercedes-Benz and Porsche joined top labor union leaders to condemn extremism and publicly express support for democracy, diversity and tolerance. At the same time, a network of small businesses started the Business for Democracy initiative and published a statement, signed by more than 300 business leaders, defending democracy and declaring that “human dignity is inviolable.” Later, the chief executive of Siemens publicly repudiated AfD policies and declared it was time to “stand up and intervene.”

The Catholic Church also responded forcefully. Representatives from all 27 German bishoprics released a statement condemning right-wing nationalism and declaring:

Right-wing extremist parties and those that place themselves close to such ideologies can be no place of political engagement for Christians. These parties are not electable . … We call on all fellow citizens … to clearly reject political offers from the far-right.

Those public declarations took place against the backdrop of the largest street demonstrations in the history of the Federal Republic of Germany. The demonstrations were organized by a civil society coalition called “Hand in Hand,” which encompassed 1,300 different organizations, including unions, churches, doctors’ associations, refugee protection agencies and even environmental groups. Millions of citizens from across the political spectrum gathered week after week in large cities and small towns in defense of democracy. Although the AfD remains very popular in several east German states, its national support has declined by approximately 25 percent since the protest movement began.

When President Bolsonaro began to threaten democratic institutions in the run-up to the 2022 election, Brazilian civil society mobilized in a similar manner. Mr. Bolsonaro threatened the Supreme Court, attacked the legitimacy of the electoral system, and sought to dismantle Brazil’s electronic voting system. This spurred business, religious and civic groups to mobilize, which produced a series of high-profile public letters in defense of democracy. In July 2022, the University of São Paulo Law School organized a letter in defense of democracy, which declared:

We know how to put aside minor differences in … defense of the democratic order … Regardless of individual electoral or partisan preferences, we call on Brazilians to remain vigilant in defending democracy and respecting election outcomes. In today’s Brazil there is no room for authoritarian backsliding.

The letter was signed by former President Fernando Henrique Cardoso, nine retired Supreme Court justices, and the heads of many of Brazil’s largest banks and businesses. As one Brazilian political scientist put it, the letter “put the issue of democracy on the election agenda.”

The following month, Brazil’s leading business association, the São Paulo Federation of Industries, spearheaded a statement, signed by the country’s Federation of Banks, its Chamber of Commerce and Academy of Sciences, the São Paulo bar association and more than 100 other organizations that defended democracy as “essential” to Brazil’s future and affirmed an “unwavering commitment to the institutions and fundamental principles of the Rule of Law.”

Finally, in October 2022, as Brazil headed into a second-round runoff between Mr. Bolsonaro and ex-President Lula da Silva, Catholic bishops from across Brazil published a “Letter to the People of God,” which called on Catholics to reject Mr. Bolsonaro. The letter declared that “staying neutral is not an option when it comes to choosing between two visions for Brazil — one democratic and the other authoritarian …. The Church does not have a political party, nor will it ever, but it does take a stand.”

Mr. Bolsonaro narrowly lost the runoff, and his effort to overturn the election results met overwhelming public rejection.

In the United States, the civic response to the Trump threat has been tepid. For a moment, business leaders seemed poised to defend democracy. After the Jan. 6 insurrection, many leading U.S. businesses announced that they would not contribute to lawmakers who voted to decertify the results of the 2020 election.

Unfortunately, most of these companies — including AT&T, Boeing, Comcast, G.E., General Motors, Home Depot, Lockheed Martin, Pfizer, UPS, Verizon and Walmart — soon abandoned their pledge. Politico identified more than 100 companies and business groups that pledged to suspend or review donations to election deniers in early 2021. More than 70 of them resumed contributions to election deniers before the 2022 midterms. Overall, ProPublica found that at least 276 Fortune 500 companies have contributed to congressional election deniers.

As the 2024 election approached, many American chief executives publicly downplayed the threat posed by Mr. Trump. Sam Altman, the founder of OpenAI, declared that “America is going to be fine … no matter what happens in this election,” while Jamie Dimon, the chief executive of JPMorgan Chase, said his company would “survive and thrive” under either party’s candidate. Mr. Dimon, who is considered influential in financial circles, has privately supported Ms. Harris but publicly declared himself undecided in the election’s final weeks.

Although many individual business leaders have worked to defend democracy, leading national business associations like the Business Roundtable and the U.S. Chamber of Commerce remain on the sidelines, refusing to repudiate Mr. Trump’s authoritarianism.

Many of America’s religious leaders have also remained quiet. Most prominent evangelical leaders have either remained silent or endorsed Mr. Trump. To give one example, although Franklin Graham claimed to be above the partisan fray, he called on his followers to “Pray for former President Donald Trump. His enemies want to do everything they can to destroy him.”

Catholic leaders have also failed to speak out. Although the U.S. Conference of Catholic Bishops issued a public statement condemning the Jan. 6 insurrection, it was, in the words of the Catholic writer Thomas Reese, “remarkably silent” in the face of Mr. Trump’s subsequent resurgence. In November 2023, the bishops conference issued an election-year document entitled “Forming Consciences for Faithful Citizenship,” as it does every four years. The letter listed abortion as a “pre-eminent priority,” but it did not mention the defense of democracy. The U.S. Conference of Catholic Bishops was sharply critical of the first Trump administration’s immigration policies, but unlike the German bishops’ response to the AfD’s mass deportation plans, it has not publicly denounced Mr. Trump’s own mass deportation plans.

The U.S. establishment is sleepwalking toward a crisis. An openly antidemocratic figure stands at least a 50-50 chance of winning the presidency. The Supreme Court and the Republican Party have abdicated their gatekeeping responsibilities, and too many of America’s most influential political, business and religious leaders remain on the sidelines. Unable to rise above fear or narrow ambition, they hedge their bets. But time is running out.

What are they waiting for?

Steven Levitsky and Daniel Ziblatt (@dziblatt), professors of government at Harvard, are the authors of “Tyranny of the Minority” and “How Democracies Die.”

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