He has jolted us to address the decay in our civic culture and institutions. (Evan Vucci/Associated Press)

E.J. Dionne Jr., Thomas E. Mann and Norman J. Ornstein are the authors of “One Nation After Trump: A Guide for the Perplexed, the Disillusioned, the Desperate, and the Not-Yet Deported,” from which this essay is adapted.

E.J. Dionne Jr., Thomas E. Mann and Norman J. Ornstein are the authors of “One Nation After Trump: A Guide for the Perplexed, the Disillusioned, the Desperate, and the Not-Yet Deported,” from which this essay is adapted.

The election of Donald Trump could be one of the best things that ever happened to American democracy.

We say this even though we believe that Trump poses a genuine danger to our republican institutions and has done enormous damage to our country. He has violated political norms, weakened our standing in the world and deepened the divisions of an already sharply torn nation.

But precisely because the Trump threat is so profound, he has jolted much of the country to face problems that have been slowly eroding our democracy. And he has aroused a popular mobilization that may far outlast him.

Many of the trends that led to Trump’s election have been with us for years; he has created a crisis by pushing them to their alarming endpoints. Political norms, for example, have been decaying for decades, but Trump has eschewed norms altogether. One reading is that there will be no going back from the diminished public life he has created, and it’s certainly true that the breaching of norms often produces a cascading effect: Behavior previously considered inappropriate is normalized and taken up by others. Yet Trump’s sheer disregard for the normal practices and principles of presidential behavior has cast a spotlight on the vital role that norms play in regulating and protecting our democracy. Only when norms disappear are we reminded of how important they were in the first place.

The steady radicalization of the conservative movement since the 1960s paved the way for Trump by undermining trust in government and promoting a sense that public officials are not interested in solving the problems of everyday Americans. This was a successful strategy for the Republican Party, but it produced the least-qualified and least-appropriate president in the nation’s history. While many Republicans remain in denial, hoping that Trump will deliver them policy victories and court seats, some of them are starting to reexamine their consciences and their long-term political interests.

A large group of influential conservative thinkers — Jennifer Rubin, Michael Gerson, Max Boot, George F. Will, Peter Wehner, William Kristol and Tom Nichols, to name just a few — has spoken out against the nativist and xenophobic strain in the Republican Party that gave rise to Trump and against his manifest disrespect for our institutions. They want a problem-solving Republican Party, a necessity for our political system to operate. Only a handful of Republican politicians have joined them, but their ranks are growing and include Gov. John Kasich of Ohio and Sens. John McCain and Jeff Flake of Arizona.

Meanwhile, Republicans' failure to pass any major piece of their legislative agenda, despite their control of the presidency and both houses of Congress, is a sign that tea partyism provides no plausible path to governing. A purely anti-government creed is out of touch with an American majority that may mistrust government but still expects it to provide significant services, social protections and help in time of catastrophe. We have seen this in the backlash to the efforts to repeal Obamacare. Republicans were scrambling this past week to pass another destructive repeal bill that would leave millions without health insurance, simply because the congressional majority is desperate for a legislative victory. But they have already lost the battle for public opinion.

The Trump era has pushed corporate leaders out of their comfort zones, too. The mass resignations of chief executives from White House business advisory groups in the wake of Trump's shamefully equivocal remarks about the violence in Charlottesville were one sign of this. So was the strong pushback — from Apple's Tim Cook, Hewlett Packard Enterprise's Meg Whitman and JPMorgan Chase's Jamie Dimon, among many others — against Trump's elimination of the Deferred Action for Childhood Arrivals (DACA) program protecting immigrants who were brought to the country illegally as children.

And Trump's victory has led to soul-searching in the media. The election was a near-perfect case study in the dangers of false equivalence, as Hillary Clinton's significant but certainly not disqualifying problems were often portrayed as more or less comparable to Trump's obvious inappropriateness for the presidency, his hateful rhetoric and his astonishingly long list of scandals. But many of the country's leading news organizations have covered the Trump White House's lying and evasions with straightforward vigor. If Trump has exacerbated the problem of media echo chambers, particularly on the right, he has also created a newly powerful constituency that cherishes a free press — witness the soaring digital circulation numbers of The Washington Post, the New York Times and many other media outlets devoted to hard-hitting reporting and analysis.

The Trump jolt has done more than force the country to a necessary reckoning. It has also called forth a wave of activism, organizing and, perhaps most important, a new engagement by millions of Americans in politics at all levels.

Large-scale demonstrations are part of the response, and so are grass-roots efforts by citizens to confront their legislators at town halls and any other venues where politicians can be found. They have won concrete victories against Trump's agenda and have changed minds, most dramatically on Obamacare. In April, Gallup reported that 55 percent of Americans approved of the Affordable Care Act, up 13 points from November. It was the first time that a majority registered a positive view of the law.

The need to contain Trump has given life to new forms of organization. People of faith, across traditions, have stood up for the most vulnerable in confronting measures that have targeted immigrants and sought to roll back social protections. Lawyers have organized to combat the president’s travel bans, to protect the rights of undocumented individuals and to challenge Trump’s financial conflicts of interest. Public interest groups such as the Campaign Legal Center, Citizens for Responsibility and Ethics in Washington and the Project on Government Oversight have expanded their efforts on behalf of political reform, forging new alliances to fight the influence of big money in politics, protect voting rights, end gerrymandering, strengthen anti-corruption statutes and challenge the electoral college.

Will these initiatives lead to a sustained, long-term project? Will they build a new politics that acts as a counter to Trumpism and survives beyond his time in office? The evidence is promising.

Many of the new groups are developing models of citizen activism designed to promote lasting engagement. The largest of these, Indivisible, started as an online guide to political advocacy from former congressional staffers, but it amassed several thousand local chapters across the country with astonishing speed, assisted by full-time organizing staff. While Indivisible chapters do take action to resist Trump’s agenda at the national level, they emphasize advocacy in their states and counties. Although Trump is doing great damage through and to the federal government, the decay in our civic culture and institutions must be addressed from the bottom up.

Swing Left, another group formed in the aftermath of the 2016 election, is helping to connect progressives living in comfortably blue districts with opportunities to support Democratic congressional candidates in nearby swing districts. And #KnockEveryDoor is recruiting and training volunteers to canvass in their communities with the goal of promoting progressive policies by engaging voters in civil conversations — imagine that! — about the issues that matter most to them.

Organizations that existed prior to Trump’s victory have reconsidered their political strategies and rededicated themselves to building the capacity of grass-roots activists. The ACLU has launched the People Power platform, an online network to train its members in activism and connect them to events in their communities. The progressive MoveOn.org launched Resistance Summer in June to educate 1,200 people in political organizing and advocacy. This was matched by a similar Resistance Summer effort within the apparatus of the Democratic Party.

To a greater degree than before, left-of-center issue-based advocacy groups are uniting behind a broad progressive agenda. At the women's marches in January, the many signs calling for gender equality and reproductive justice were joined by placards opposing voter suppression, defending the Affordable Care Act and supporting the Black Lives Matter movement. This ecumenical spirit has continued. And when Trump announced his decision to repeal DACA earlier this month, a diverse coalition including the NAACP, the Human Rights Campaign, Planned Parenthood, People for the American Way and the Sierra Club joined immigrant rights groups in condemning the president's action. After many years when activists often focused on their own particular causes, we're seeing a tilt away from single-issue politics toward multi-issue coalition building.

These displays of solidarity are significant in the short term because the anti-Trump movement is much stronger when it overcomes internal divisions. They demonstrate that the tensions that have surfaced on the left and within the Democratic Party, between supporters of a progressive economic vision that appeals to working-class white voters and supporters of a politics aimed at traditionally marginalized communities, are predicated on a false choice. It’s worth remembering that the great civil rights march of 1963 was organized under the slogan “jobs and freedom,” linking economic rights to racial justice. These concerns must be seen not as mutually exclusive but as mutually reinforcing.

Perhaps the clearest sign of long-term commitment has been the surge in the recruitment of candidates for public office, especially among younger activists who can speak effectively to peers turned off in the past by political action.

Emily’s List, which trains and funds pro-choice Democratic women running for office, says it has already had more than 18,000 potential candidates seek its assistance ahead of the 2018 midterm elections, compared with fewer than 1,000 in the last election cycle. To address racial and gender disparities in politics, Higher Heights is working to recruit more black women to run for office. A new group called Run for Something is focusing on electing young progressives to state and local offices by publicizing their campaigns and connecting them with potential volunteers and donors. It announced its first batch of endorsements in August.

A broad and powerful movement has arisen to defeat Trump and Trumpism. Its success will be a triumph worthy of celebration.

But this is not just an end in itself. It is also an essential first step toward a new politics. It will be a politics that takes seriously the need to solve the problems Trump has exposed. It will nurture our dedication to the raucous but ultimately unifying project of democratic self-government. For it is our shared commitment to republican institutions and democratic values that makes us one nation.

Twitter: @EJDionne

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