The National Environmental Policy Act, which was signed into law by President Richard M. Nixon more than 50 years ago, is so foundational to environmental law that advocates refer to it as the “Magna Carta.” It’s also despised by many conservative politicians and pro-business types, who view its rigorous environmental review processes as an impediment to growth.

So, of course, the Trump administration, which has been all but a wrecking ball on matters of regulation, is trying to weaken it.

Well, not so fast.

On Friday, attorneys general from 21 states joined together to sue the Trump administration to stop changes finalized last month, changes that would put a hard-time deadline on environmental reviews of major federal infrastructure projects. “This is just another case where they are trying to violate long-standing, established environmental policy,” California Attorney General Xavier Becerra (D), who is taking the lead in the case, told me recently.

It’s pretty much just another day in the office for Becerra. A little over a year ago, he filed California’s 50th lawsuit against the Trump administration, smashing the record held by Texas, which took the Obama administration to court 48 times over two terms. Since then, Becerra has filed another 50, including the one to overturn changes to NEPA.

The legal battles were easily foreseen. Trump campaigned for president promising to take on excessive government rule-making. He would, he said, “get rid of wasteful rules and regulations which are destroying our job creation capacity” and claimed he would do so “very, very quickly.” In office, his administration has approached the issue of overturning previously enacted regulation like a smash-and-grab robber, showing little concern for either precedent or continuity, never mind the impact on actual Americans.

The governments of blue states have fought back, filing lawsuit after lawsuit, often in multi-state actions. “This activism has complicated the president’s agenda in many areas from immigration to the environment,” Paul Nolette, an associate professor of political science at Marquette University who tracks the filings in an online database, told me.

The ongoing battles have turned Becerra, the son of Mexican immigrants and a first-generation college graduate, into something of a resistance hero. In another joint lawsuit, California successfully challenged Trump’s rescinding of Deferred Action for Childhood Arrivals at the Supreme Court, and the state will take the lead in defending the Affordable Care Act when that case reaches the nine justices this fall.

About half the suits California has filed against the government relate to the environment. It has sued the Trump administration over rollbacks of vehicle gas mileage standards and over the revocation of California’s long-held right to set higher air pollution and fuel efficiency standards than those of the federal government. “For more than 50 years, California has been leading the pack,” Becerra told me. “We think history is going to prove we’re on the right track.”

The laws and regulations Trump is trying to take apart — from the environment to those that impact immigrants to the United States — are all but essential to the future of his state, Becerra told me. “California is all about leaning forward, not backsliding,” Becerra told me. He points out that 1 in 4 “dreamers” lives in the state.

Becerra said he didn’t sign up to be an AG expecting to sue the Trump administration 100 times — but he did figure it would happen a lot. That, he said, is why he was willing to give up his seat in Congress, where he represented a chunk of Los Angeles for more 20 years, to take the job Kamala D. Harris left when she was elected to the Senate in 2016. “I figured I’m going to have a chance to make a big difference,” he said. “I knew we would be busy if [Trump] took on even a fraction of what he said he’d do during the campaign.”

Becerra’s now getting mentioned for a possible position in a Biden administration, should it come to pass. His name also circulates on short lists to be appointed to the Senate seat Harris would vacate if she becomes vice president. Would he take either? It sure sounds like it. “Where can I make the biggest difference, that’s what I’ll take a look at,” he told me.

Here’s hoping Becerra will have options. Trump has attempted, for 3¾ very long years, to take our nation backwards, to a time when corporations ran roughshod over the environment with little to stop them, and women and people of color enjoyed much less in the way of rights. The November election is our chance to stop Trump before it’s too late to undo the damage his presidency has caused. It’s good to have the courts to enforce the law when the president will not. It will be even better when we don’t need to turn to them to stave off yet another Trump disaster.

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