The city of Los Angeles has declared itself a sanctuary city, where local authorities do not share information with federal immigration enforcement. But L.A.—where nearly forty per cent of residents are foreign-born—became ground zero for controversial arrests and deportations by ICE. The Trump Administration deployed marines and the National Guard to the city, purportedly to quell protests against the operation, and the Secretary of Homeland Security, Kristi Noem, spoke of the government’s intention to “liberate” Los Angeles from its elected officials. This week, David Remnick talks with the city’s mayor, Karen Bass, a former congressional representative, about the recent withdrawal of some troops, and a lawsuit the city has joined arguing that the Trump Administration’s immigration raids and detentions are unconstitutional. (A federal judge has issued a temporary restraining order against the government.)  “I’ve described L.A. as a petri dish,” Bass says. The Administration “wanted to . . . show that they could come in and do whatever they wanted, whenever they wanted, and however they wanted. They were putting every other city in America on notice: ‘mess with us will come for you.’ ”