Congress is confronting renewed scrutiny over the cost of immigration detention operations at Guantanamo Bay Naval Base, with a recent CBS News investigation finding that more than $70 million from the Department of Defense alone has been spent housing migrants transferred from the United States since February 2025.
The operation, known as Operation Southern Guard, marks the first time individuals have been transported directly to Guantanamo from the U.S. mainland. According to congressional sources and reporting by CBS News, approximately 832 immigrants have been held at the facility under conditions that have drawn criticism from human rights organizations and Democratic lawmakers.
A December report released by Sen. Elizabeth Warren (D-Mass.) and Rep. John Garamendi (D-Calif.) found that the Department of Defense obligated well over $2 billion on immigration enforcement in 2025, including border security operations and detention programs that diverted funds from military construction projects.
What the Right Is Saying
Administration officials and Republican lawmakers have defended the Guantanamo operations as necessary tools for immigration enforcement. Secretary of Defense Pete Hegseth said in February 2025: "The message is clear: If you break the law, if you are a criminal, you can find your way at Guantanamo Bay. You don't want to be at Guantanamo Bay, which is where we housed al Qaeda after 9/11."
Senate Republicans are simultaneously working on additional funding for Trump's anti-immigrant agenda, proposing another $72 billion through 2029 beyond the $170 billion already appropriated last year.
Conservative supporters argue that strong border enforcement measures deter illegal immigration and protect national security. Defense officials have maintained that the infrastructure at Guantanamo provides necessary capacity during migration surges, though CBS News reports that tent facilities built to hold 30,000 migrants at a cost of $3 million remain unused.
General Francis L. Donovan, commander of U.S. Southern Command, testified in March before the Senate Armed Services Committee that SOUTHCOM would "set up a camp" at Guantanamo Bay "to deal with those migrants" in the event of a migration surge from Cuba — language that framing advocates say underscores the administration's commitment to border security.
What the Left Is Saying
Progressive Democrats and human rights advocates are calling for an immediate end to detention operations at Guantanamo Bay. Thirty-one members of Congress, led by Rep. Delia Ramirez (D-Ill.), have sent letters urging the administration to terminate the program, which they describe as wasteful and inhumane.
"Congress must stop writing blank checks for cruelty," wrote Yumna Rizvi, senior policy analyst at The Center for Victims of Torture, in a recent opinion piece. "It should end detention at Guantanamo — ensuring the base is never used for detention of any groups again — and demand accountability for the wasteful spending rather than acquiesce under the guise of national security."
Sen. Warren has pointed to the $70 million price tag as evidence of fiscal irresponsibility, noting it exceeds by $20 million the amount identified in December's congressional report and $10 million more than figures cited in a joint State Department and Defense Department Inspectors General report from February.
Over 80 U.S.-based and international civil society organizations have joined the call, citing the base's history as a site associated with indefinite detention without trial and what the United Nations has described as "ongoing cruel, inhuman, and degrading treatment."
What the Numbers Show
According to CBS News reporting and congressional documents, over $70 million has been spent on migrant detention operations at Guantanamo since February 2025 — this figure covers only Department of Defense expenditures and does not include amounts from the Department of Homeland Security.
The December congressional report by Sens. Warren and Garamendi documented that DOD obligated more than $2 billion for immigration enforcement in 2025, including funds diverted from military construction projects to support DHS operations through the fall.
Historical data shows significant costs associated with Guantanamo's post-9/11 detention program: Since 2002, approximately 780 detainees have been held at the facility, most without charge or trial. The Center for American Progress estimated cumulative costs reaching $5 billion by 2013, with annual operating expenses historically running around $500 million.
Currently, about 600 government employees — including Immigration and Customs Enforcement personnel and non-military staff — are stationed at Guantanamo to manage detention operations, producing a staff-to-detainee ratio of approximately 100 to 1. Fifteen men remain in indefinite military detention at the facility.
The December Senate report noted that detention at Guantanamo is far costlier than domestic facilities due to travel costs, supply chain expenses, personnel requirements and maintenance of aging infrastructure.
The Bottom Line
Congress faces competing pressures as it considers future immigration enforcement funding: fiscal conservatives concerned about expenditures exceeding initial projections, human rights advocates demanding an end to what they characterize as wasteful spending on operations with limited deterrent effect, and administration officials defending the measures as essential border security tools.
The $70 million figure for Guantanamo detention represents a small fraction of the broader $2 billion-plus in immigration enforcement costs documented by congressional investigators, but critics argue it exemplifies systemic waste. Supporters counter that maintaining capacity for surge scenarios serves legitimate national interests.
What to watch: Whether additional oversight hearings are scheduled on immigration detention costs, whether the 31 House members pushing for program termination can build broader bipartisan support, and how Senate Republicans' proposed $72 billion in future funding addresses detention facility expenditures.