President Trump. (Kiichiro Sato/Associated Press)

Eric Liu, founder of Citizen University and executive director of the Aspen Institute Citizenship & American Identity Program, is the author of “You’re More Powerful Than You Think: A Citizen’s Guide to Making Change Happen.”

As Donald Trump approaches the 100th day of his presidency, let’s give him credit: He has sparked one of the greatest surges of American citizen action in half a century. Indeed, this burst of civic renewal may be more enduring than anything else he has done in his chaotic first months on the job.

For decades, civic educators and activists have wondered what it would take to get a greater number of Americans more involved in self-government. All it took, it turns out, was a bombastic, authoritarian, nativist president whose erratic behavior and executive overreach made him a vivid threat to democratic norms and the Constitution.

All across the country, in red and blue precincts alike, many Americans are for the first time joining civic clubs, publishing newsletters, creating political reading groups, organizing rallies, lobbying lawmakers and relearning the basics of how a bill becomes a law — or how a court can block an executive order.

To be sure, President Trump didn’t intend to generate this civic surge. And he tries at every turn and in every tweet to play down or discredit it. But it nonetheless is the most concrete way that Trump thus far has made America great again: He has awakened millions of people to become active participants in civic life rather than passive spectators.

The nationwide science marches, tax marches and women’s marches are one measure of this great awakening. So are the rallies in defense of Trump. So is the influx of dollars and volunteer hours to groups such as the American Civil Liberties Union or the Southern Poverty Law Center. So, too, is the phenomenal growth of Indivisible, which began as a Google document written by ex-congressional staffers on how to pressure a member of Congress and has now spawned more than 6,000 self-organized local chapters. This is a new and durable force in American politics.

Though much of the new civic engagement is negative — activated, that is, by a desire to resist or block Trump and his agenda — there is no question that Americans left and right are developing civic muscles that can be put to many uses for many years.

(Claritza Jimenez/The Washington Post)

Indeed, it’s important that many agendas emerge. A single centralizing force such as Trump is best neutralized not with a single source of opposition but with a swarm of countervailing forces, like antibodies to a virus or Lilliputians to a Gulliver.

This is why libertarians are speaking out against Trump’s casual but menacing suggestions that protest be punishable or the rights of criminal suspects abridged. Meanwhile, social justice progressives and pro-business conservatives both are pushing back as Trump officials propose capping legal immigration. And frustrated Trump voters are organizing to hold their man to his “America First” pledge as he gets the United States more entangled in conflicts abroad.

All across the political spectrum, people are taking this opportunity — now that we are appreciating anew the importance of civics class — to hold public debates in every setting possible about the balance of responsibilities between citizen and state.

Most of all, this is a moment for people on the left and right alike to find common interest in strengthening the habits of local self-government. Calling members of Congress is great. Sharing email alerts about the president is necessary. But as the ACLU’s #peoplepower campaign has been showing in thousands of local gatherings, we all can have far more direct civic impact by becoming literate in the power structures of our own cities, counties and states.

Indeed, the civic surge of the Trump era reminds us just how much the local matters — a lesson the right has generally understood better than the left. The local is where citizens can practice power every day — not just in resistance but in creation — and see the results of our actions and omissions.

The framers of the Constitution knew that local militias, rooted in their communities, were motivated to defend liberty not as an abstraction but as a face-to-face experience. We are seeing today the spontaneous emergence of networks that are like civic militias: locally rooted webs of citizen lawyers, citizen journalists, citizen scientists, citizen artists and citizen preachers, self-organizing to defend freedom on a moment’s notice.

We have Trump to thank for this. We can show him our gratitude by further limiting his ability to do harm — and further bolstering our ability to repair the republic.