Over a million people marched last Sunday at women’s rallies in the Bay Area and Los Angeles, to say nothing of the dozens of other rallies across the states.

Governor Jerry Brown uses his State of the State to vow a legal fight if Washington, D.C. tries to roll back California’s stand on clean cars.

Shortly after the President signed an executive order threatening federal funds to “sanctuary cities,” Los Angeles Mayor Eric Garcetti released a statement not backing down on the city’s commitment to protecting all of its residents, even its undocumented ones. Mayor Lee of San Francisco and other Bay Area leaders made similar declarations.

The statements echo an op/ed written by Streetsblog Editor-in-Chief Benjamin Fried who, days after the November election, urged New York’s leaders not to cut deals for federal funds that come with strings attached that undermine progressive values on immigration.

So far, California’s people and elected leaders are talking the talk. But the threat of withholding federal funds to governments that refuse to actively support the president’s positions on immigration is designed to weaken those bonds over time.

It was only two days ago that Garcetti thundered, “Splitting up families and cutting funding to any city — especially Los Angeles, where 40 percent of the nation’s goods enter the U.S. at our port, and more than 80 million passengers traveled through our airport last year — puts the personal safety and economic health of our entire nation at risk.” But just yesterday another statement from the Mayor’s Office celebrated a $30 million federal “Promise Neighborhood Grant” for educational and community-based services to help low-income children and families.

What happens if the federal government withholds that grant until the LAPD agrees to engage in deportation activities? How about if Trump threatens to undermine the city’s Olympic 2024 bid? Or when it threatens to withhold funding for the Purple Line extension?

Similarly, the federal government has many obligations to California–the state hopes to secure billions more for California High Speed Rail, for example. Garcetti, Lee, Brown and their successors will be tested. There are many legal opinions from around the country stating that Trump’s executive order is more bluster than substance, but even so, funding for crucial projects could be held up for years as the courts work things out. Even then, given the makeup of the Supreme Court, legal precedents can change.

The idea of holding federal dollars hostage over disagreements on immigration enforcement is, at best, a plan to divide residents from their leaders and citizens from new immigrants.

The battle over the EPA and Climate Change is off to a less-fierce start, but it could turn into a major battle over the right of states to regulate the environment within their borders. The target would likely be California’s decades-old fuel-efficiency standards or the more recent “clean car” standards. The federal government has rarely challenged California’s laws, but Brown is still gearing up for a fight.

So when it comes to being the beachhead for resistance against scary changes to our national laws on Climate Change and Immigration, so far California is holding to its promises.

But this is just the first week. There are, at least, 207 to go.