It has been 25 years since the attacks of Sept. 11, and 9/11 immigration enforcement remains one of the most enduring shifts in U.S. policy. Nearly 3,000 people were killed in 2001, and the response reshaped how the nation views and polices immigration.
Experts say the mass deportation push under President Donald Trump, which resulted in more than 40,000 arrests in June and July, is unprecedented in scale. They also note it is the product of a post-9/11 transformation that recast immigration from a civil regulatory system to a component of counterterrorism and national security.
9/11 immigration enforcement and the birth of DHS
Before the attacks, the Immigration and Naturalization Service, housed in the Justice Department, managed border enforcement, removals, and applications for status and citizenship. Neither the Department of Homeland Security nor Immigration and Customs Enforcement existed.
Doris Meissner, who led INS from 1993 to 2000, said national security was not the agency’s central mission during her tenure, despite high-profile incidents like the 1993 World Trade Center bombing. She recalled that intelligence and enforcement agencies operated in tight silos, with limited information sharing considered a safeguard for civil liberties.
The 9/11 plot exposed the costs of those silos, particularly after it emerged that the hijackers held valid visas issued by INS. Journalist Garrett M. Graff noted that INS processed paperwork for two hijackers and even notified a Florida flight school months after the attacks that approvals for training had been granted. That failure accelerated the push to reorganize.
Congress answered with the Homeland Security Act of 2002, which dissolved INS and created three agencies: ICE, Customs and Border Protection, and U.S. Citizenship and Immigration Services, all under the new DHS. This embedded immigration enforcement within a national security framework and significantly expanded resources.
Budgets, militarization, and deportations surge
INS had a $4.3 billion budget in 2000. By 2006, DHS immigration enforcement agencies collectively reached $12.5 billion.
The infusion of funds and a security-first mission altered border operations. Graff said Border Patrol was much smaller before 2001 and carried out limited, targeted enforcement. The agency was also less militarized, with long guns not typically used on routine patrols.
Deportations climbed sharply. In the decade before 9/11, the U.S. deported 1.6 million people. In the decade after, that figure rose to 2.3 million.
Debate over scope and power
The rapid expansion of federal homeland security authority drew early criticism as overly broad. In 2014, a libertarian policy analyst at the Cato Institute argued DHS had grown bloated by leveraging fears of terrorism and had extended federal police power into areas where it did not belong.
Those debates have renewed relevance as ICE has become the highest-funded federal law enforcement agency during Trump’s second term and a key driver of his mass deportation strategy. The post-9/11 framing of immigration as homeland security remains central, with the administration repeatedly citing terrorism and national security risks to justify policy.
Jorge Loweree of the American Immigration Council said the significance of the post-9/11 system is not only the power of immigration agencies themselves, but also their ability to draw support from across the federal law enforcement landscape and from local police. He described it as an enormous dragnet with the aim of sweeping in as many people as possible.
Those debates have renewed relevance as ICE has become the highest-funded federal law enforcement agency during Trump’s second term and a key driver of his mass deportation strategy, echoing legal and political battles such as when a judge halts Trump’s latest birthright citizenship order.
2 Responses