President Trump’s budget proposal—a fiscal assault on everything other than rich people and the military—could prove to be progressives’ ultimate trump card. With its deep cuts to vital programs and protections for low-income and working-class people, including Trump’s own voters, it lays bare the scope of his destructive agenda.

Despite its dubious prospects for passage (even some Republicans are declaring it dead on arrival), Trump’s budget could be progressives’ best arsenal for sustained mass resistance. It’s time for a “fiscal fightback” that builds nationwide awareness and resistance—one that fuels progressive electoral and policy alternatives for 2018 and beyond.

Trump’s budget ramps up military and border patrol spending while cutting hundreds of billions from antipoverty programs—cuts that “would hit hardest many of the economically strained voters who propelled the President into office,” The New York Times reported. This includes, over the next decade, “slashing more than $800 billion from Medicaid, the federal health program for the poor, while slicing $192 billion from nutritional assistance and $272 billion overall from welfare programs.”

As moral documents, budgets elucidate political vision and priorities better than any rhetoric. Trump’s budget, titled “A New Foundation for American Greatness,” is no aberration; it fits neatly with the longstanding GOP agenda of enriching the wealthy while making poor and working-class people more economically desperate and exploitable.

The budget calls for erasing many highly popular programs serving working-class and low-income people. This lengthy list includes the Legal Services Corporation, which provides essential legal aid to poor people; the Appalachian Regional Commission, which helps create economic opportunities in this chronically impoverished region; the USDA’s Rural Economic Development Program; the Low Income Home Energy Assistance Program that helps poor people get heat and electricity; and programs that provide job training, and worker health and safety training grants that help workers throughout the country.

Trump’s budget would also mean major cuts in federal funds to states—something even many Republican governors and representatives object to. Progressives should relentlessly hammer home the human effects that Trump’s budget will have on communities across the United States, and offer concrete alternatives to help poor, working, and middle-class Americans create a real future for themselves and their children.

We need an aggressive, fact-driven, and sustained fiscal fightback in every congressional district across America. This could include sustained protests, mass phone calls and emails, district-level town halls, and voter education both to resist the GOP budget, and to fuel a progressive populist groundswell for 2018 and 2020.

There’s a ready-made alternative that Democrats and others can run on—what the Congressional Progressive Caucus calls a “roadmap for the resistance,” also known as the “People’s Budget.”

With its populist frame of moving America “from Austerity to Prosperity,” the People’s Budget provides for massive infrastructure and public works job-creation, promising 8.4 million “good paying jobs by 2018.”

While Trump’s budget proposes a mirage of 3 percent growth by gutting government regulations and gifting huge tax breaks for the rich and corporations, the People’s Budget would invest $1.9 trillion—including direct job creation for communities to rehabilitate parks and public lands, expand early childhood development programs, and upgrade public education infrastructure and staffing.

While Trump’s plan slashes worker safety and job training programs, and eviscerates food stamps (SNAP) and other life-preserving supports for poor people, the People’s Budget beefs up labor protections so America’s workers don’t get injured or stiffed on the job so frequently. It also expands food stamps and child nutrition funding—which studies repeatedly show provide a Vitamin-B-like boost to public health and local economies.

Instead of Trump’s trickle-down tax breaks for the wealthy and big business, the People’s Budget restores modest Clinton-era tax rates on millionaires and billionaires, bringing in job-creation revenue while making the economic playing field at least a bit more level. The People’s Budget expands opportunities, stimulates local economies, and invests in America’s future—roads and bridges, health and education, workers’ wages and safety, and environmental sustainability.

Fiscal politics may not be sexy, but it’s precisely the kind of bread-and-butter, meat-and-potatoes politics that Bernie Sanders championed to great success in 2016. The coming budget battle marks a vital opportunity to remind voters everywhere that this is not a contest between more or less government, but about which government, and for whom.

The Trump and Republican budgets tell voters a story about their real priorities, their real base. It’s up to progressives to make that story abundantly clear, and to provide voters an alternative vision—a “roadmap” for a government and an economy that serves human needs, aspirations, and our future.