What to Know About DHS’s Threat to Stop International Flight Processing at Sanctuary City Airports

The Trump Administration is “drawing up plans” to halt the processing of international flights at airports in sanctuary cities, according to Homeland Security Secretary Markwayne Mullin.

Mullin said on Fox News on Tuesday that the Administration is “not initiating” the effort “yet,” but that it is “currently drawing up plans” for such a move. His remarks came in response to protests outside an immigration detention facility in Newark over the Memorial Day long weekend, which he condemned.

“In these sanctuary cities where the local, radical left Democrats aren’t allowing us to do our jobs and enforce federal laws, then we shouldn’t be processing international flights into their cities either,” Mullin said. “They don’t want us to enforce immigration but they want us to process immigration at their facilities? Nothing about that makes sense to me.”

Read More: What Are Sanctuary Cities and Why Is Trump Targeting Them?

Mullin, who President Donald Trump tapped to replace Kristi Noem as the head of the Department of Homeland Security (DHS) in March, has floated this idea before. Last month, he condemned sanctuary cities, saying, “If they’re not enforcing immigration laws, then why would I be processing immigration in their city?” And earlier this month, he met with executives in the airline and travel industries and said that he was considering cutting back on Customs and Border Protection staffing at airports in sanctuary cities, according to multiple news reports.

If the Trump Administration follows through on the move, it could throw air travel—and tourism—at major airports across the country into chaos. It’s not clear how the Administration halting international flight processing in some cities would work in practice, but here’s what we do know.

What are sanctuary cities?

Sanctuary jurisdictions are communities that have implemented policies that restrict the degree to which the local government can share information or cooperate with federal immigration agents. The specific policies vary depending on the city. Many Democratic-led cities across the country are sanctuary cities, including New York, Chicago, San Francisco, and Los Angeles.

Since Trump took office for a second term, he has made aggressive immigration policies a key focus of his agenda, including by targeting sanctuary cities. On his first day back in office, he signed an Executive Order, in which he said that the Attorney General and Homeland Security Secretary should ensure that sanctuary cities “do not receive access to Federal funds.”

What airports could be impacted?

Mullin has not publicly said which cities or airports the Trump Administration is looking at. But last year, the Justice Department released a list of sanctuary cities, counties, and states that it claimed had “policies, laws, or regulations that impede enforcement of federal immigration laws.” 

Many of the cities on the list have major international airports, including Boston, Chicago, Los Angeles, New York City, Newark, and San Francisco. New York’s John F. Kennedy International Airport, Los Angeles International Airport, Newark Liberty International Airport, Chicago O’Hare International Airport, and San Francisco International Airport are among the busiest U.S. travel hubs for international flights, according to the online aviation publication Simple Flying.

Mullin’s comments on Fox News sparked widespread controversy and concern. Juliette Kayyem, who worked at DHS under former President Barack Obama, condemned Mullin’s proposal.

“Of all the bad ideas floated by this Administration, this one ranks,” Kayyem said in a post on X. “Planes don’t divert to other airports. The flights will be cancelled, disrupting blue and red voters, impacting the airlines, and having no impact on immigration policy.”

Aaron Reichlin-Melnick, a senior fellow at the American Immigration Council, said the move would cause chaos.

“This plan is actively insane,” Reichlin-Melnick said in a post on X. “Airlines cannot divert large numbers of international flights from one city to another; they’d just have to cancel flights en masse, causing enormous economic damage that splashed waaaaay beyond a few big cities that were the target.”