As millions of Democrats, Greens, liberals, progressives, and lefties across America prepare to resist Trump, it’s time to build greater unity and alliances among this vast rainbow of people, communities, and movements. With heightened attacks on immigrants, women, people of color, Muslims, the environment, workers’ rights, and more, we simply cannot afford political isolation and fracturing.

Imagine a national strategic alliance around shared principles and priorities that could collectively mobilize tens of millions of people to support and defend human rights, economic justice, and environmental sustainability. Protests, petitions, and grassroots meet-ups are a great start, but they are not enough for the task at hand. Now more than ever, all those wanting an egalitarian, racially just, and sustainable society fueled by participatory democracy need to forge a broad united front.

A new alliance would enable groups to retain their turf and integrity while joining forces on specific campaigns, such as the Standing Rock/Dakota Access Pipeline struggle and upcoming battles with Trump and the Republican Congress. Together, we could promote a bold progressive populist agenda while opposing rightwing and centrist policies from both major parties.

Think of the array of generally like-minded groups and initiatives across the country, which together count tens of millions of members or supporters: Our Revolution, Brand New Congress, Working Families Party, Progressive Democrats of America, Democracy for America, the Green Party, and many other regional, state, and local groups. These could unite on core goals and principles, agreeing to support each other’s efforts and collaborate whenever possible.

It’s time to think big. Let’s push the Democratic Party in an unapologetically progressive direction and build up electorally independent alternatives. This is no time for fracturing. Progressives need a coherent strategy that remains independent of the corporate, centrist Democratic Party, and that can wield direct pressure and power. Participating groups will continue to have differences, some likely never resolved—but they can still work together whenever possible.

The left must also build a new media movement to reach mainstream America, including Trump’s America, with accessible fact-driven journalism. One good start would be expanding on The Progressive magazine’s Media Project with an initiative to reach readers in battleground states, through legacy and social media, with op-eds that inform people about the concrete human and environmental impacts of the Trump-Ryan agenda.

The right has been successful at building a media network to tilt voters its way; it’s time for a major independent progressive media push, backed by real dollars, that can get out stories and op-eds beyond the leftwing echo chambers.

“The best alliances are going to come together around the biggest ideas for change,” says Becky Bond, a top adviser and organizer on Bernie Sanders’s campaign, and coauthor with Zack Exley of the new book Rules for Revolutionaries. “An alliance around a big agenda that embraces economic populism and racial justice could create a wave of victories in 2018.”

Much of this alliance building may take shape first on state and local levels, and around specific individual campaigns. Bill Fletcher, former president of TransAfrica Forum and a longtime labor leader, advocates a “fifty-state strategy for progressives. We have to anticipate all kinds of attacks, including repression,” he says. “We need to be thinking in each state, what is the road to power?”

Shannon Jackson, director of the Sanders-inspired Our Revolution, sees growing interest in progressive alliances:

“The recent victories to defeat the Trans-Pacific Partnership and against the Dakota Access Pipeline at Standing Rock are ideal examples of what is possible when people come together. It is Our Revolution’s responsibility to help strengthen the active collaboration and unification that is essential to these great successes.”

Progressive alliances “will need to be organic so that we can create an environment where many different ideas are allowed to thrive,” argues Brand New Congress co-founder and organizer Saikat Chakrabarti. “We need to bring the fight on multiple fronts at once. We need organizations that are focused on direct action, organizations that are focused on building local political power, organizations focused on building national political power, and organizations focused on creating a new media.”

The Working Families Party and other national groups have helped to organize local emergency community meetings across the country (one drawing about 1,000 people), where people can connect and organize. Groups endorsing this effort include 350.org, the Center for Popular Democracy, the Courage Campaign, Iraq Veterans Against the War, Friends of the Earth, CODEPINK, and Public Citizen.

These grassroots meetings focus on “activities everyone can take locally to protect communities and defend democracy,” the Working Families Party explained in response to my inquiry. “People are developing substantive plans for fighting back against Trump’s cabinet and agency appointments, taking action around the Inauguration, protecting the status of sanctuary cities, and standing in solidarity with communities under attack, including immigrants and Muslim Americans.”

At one of these meet-ups I attended recently in San Francisco, hundreds of people stayed late on a Friday evening discussing actions and strategies. Focus groups peeled off to discuss such topic areas as climate change, women’s rights, media democracy, and electoral strategies. The commitment and energy were palpable.

But what felt missing, at least from this gathering, was a larger political movement strategy to connect people with existing groups—local, state, and national—rather than reinventing the wheel. Despite the impressive organizing and sense of urgency, there was little talk of bolstering larger alliances, or further stitching together the movement apparatus of the progressive left.

Of course any alliance, even a nonbinding one that doesn’t intrude on turf or funds, presents challenges. Significant divides on the left, some intensified in this past election, cannot be shrugged off.

Greens and Democrats have longstanding tension and often enmity. The labor movement has many rifts, spanning union members’ support for Sanders, Clinton, and Trump. Given the ongoing debate over who is to blame for Trump’s election and what it means for Democrats and the left, it is clear that “we” will not all agree on a single path forward. Reformists, revolutionaries, liberals, and radicals have scuffled for centuries over how to address inequality, exploitation, and the consolidation of wealth and power.

Not everyone will join these new alliances, but the more who do, the better. As a longtime journalistic observer and participant in left-progressive movements, I believe the Trump moment—how it came about and the dangers it poses—highlights the need for broad, far-reaching rapprochement on the left. Groups and movements sharing progressive aims must figure out how to work together where they agree, even when they disagree on other things.

There are at least partial models for this around the country. In California, the Richmond Progressive Alliance, made up of labor, housing, environmental and racial justice groups, has won many local victories; the Progressive Leadership Alliance of Nevada brings together dozens of institutions, including labor unions, the NAACP, Sierra Club, Planned Parenthood, and others. Numerous local, state, and regional coalitions are sprouting up—and a national alliance could bring yet greater power, resources, and profile to progressive causes and movements.

The potential for unity is heightened by Trump’s prolific threats to so many communities and causes. The more people his policies offend, the bigger and stronger the resistance. For instance, Fletcher notes, there is concern in labor circles that the Trump Administration will try to undermine the Davis-Bacon Act, which requires prevailing wages be paid on publicly contracted jobs. This could potentially unite more conservative building trades unions with left-liberal unions.

Trump’s attacks on workers and unions could play a lead role in his undoing. His first tweet-promoted “win” as President-elect, the Carrier plant jobs deal in Indiana, backfired when it was revealed that the deal would allow hundreds of jobs to go to Mexico while costing the state more than $7 million in corporate tax perks. Trump’s subsequent tweet-lashing of Chuck Jones, president of United Steelworkers Local 1999, ignited bipartisan criticism that could begin to erode his working-class support. A blue-collar backlash could turn the tables against Trump, and progressive labor unions can help lay the groundwork for that.

Trump’s cabinet picks and his emerging policy agenda are already uniting millions in outraged opposition. Groups and communities are holding emergency meetings and creating rapid response networks to defend people under attack. The challenge now is to weave this tapestry of resistance into a movement that can create legislative and electoral wins.

The protests and social media eruptions will be YUGE. We must harness this into a coherent and sustainable rebellion. A working-class backlash and a smart alliance among the diverse constituencies that make up the progressive majority in this country could lead to a big midterm repudiation of the Republicans at the polls, state-level victories, and the birth of a broad-based and effective progressive movement. This is no time to squabble among ourselves or work separately—and there’s no time to lose. It’s time for progressive unity.