Now that Democrats have reached an agreement to pass a new trade deal negotiated by Donald Trump, we seem to be at last grappling with a hard truth: Our own failed policy enabled his rise in the first place.

Our party has spent 30 years failing to live up to our values on trade, and the contents of the new United States-Mexico-Canada Agreement are a litmus test on what we’ve learned. Over the past few days, we’ve seen real signs that Democrats have finally fought for workers at the negotiating table. It’s a lesson we should have learned long ago.

In 1994, President Bill Clinton signed the North American Free Trade Agreement — which most people know by its acronym, NAFTA, often used as an epithet — telling American workers that the gains from the bipartisan agreement “would be your gains, too.” The gains never came, but pink slips did. NAFTA — backed by a Democratic Party that prides itself on fighting for working people — cost the United States around 850,000 jobs.

We lost the hearts and minds of auto workers in Michigan and factory workers in Ohio who felt their own government had abandoned them. Two decades later, you can draw a direct line among those disconnected workers, their hollowed-out communities and the fears that Trump manipulated on his way to the White House.

Five months ago, it seemed like we were destined to repeat the same mistakes on the USMCA — when this deal dangerously resembled NAFTA 2.0 and I called for us to walk away.

But we have reason to be optimistic about this week’s news. The deal brokered by the Democrats reportedly forced the Trump administration to include hard-fought wins for working people: More enforceable worker protections, environmental protections and built-in measures that would improve U.S. auto workers’ wages. It also includes enforcement that Sens. Sherrod Brown, D-Ohio, and Ron Wyden, D-Ore., have called for to ensure that Mexico inspects factories with poor working conditions, and allow us to stop and inspect goods at the border. The impact of both would go well beyond the border, lifting up all American workers in a fairer system that doesn’t encourage a race to the bottom.

But the ink isn’t dry on the yet-to-be-released text — and the devil is in the details.

If the reports are true and the USMCA includes all of the above, it’s a success. That's a deal that puts working people first — one that drives fair wages, safer working conditions and allows organized labor to grow in Mexico. That's a deal that, for the first time in American history, is written with workers guiding the pen.

But if Trump pulls a bait-and-switch, or Democrats are asked to settle for less, we should still be ready to walk away.

It will take political strength to get us out of the broken system in which we have been stuck for too long — one that puts multinational companies ahead of workers.

In New York City, we have made the kinds of changes that put workers ahead of corporate profits. We guarantee workers paid sick leave. We have a $15 minimum wage. We have fair scheduling laws that require employers to give their employees consistent and predictable hours, whether they work in a fast-food restaurant or a corporate office. We have a strong local enforcement agency that not only protects workers, but also looks out for the very rules that protect them.

We’ve seen here how these changes lift up lives, and restore working people’s belief in government.

When Democrats settle for something less, though, we all now know what happens. New Yorkers and all Americans live daily with the legacy of NAFTA and the 2016 election result it caused. Every disastrous Trump policy — from tax breaks for billionaires, to ripping away health care from people who need it, to inaction on climate — should remind us that we cannot lose working people's trust again, or the whole country will suffer.

Democrats need to keep fighting on the USMCA until we verify that we have got what we wanted — or we should let Trump's deal fail.