To mark its fifth anniversary, Stephen E. Flynn, CFR’s leading national security expert, evaluates the general performance of the Office of Homeland Security.

The Bush administration’s approach to the detention and prosecution of prisoners held at Guantanamo Bay, Cuba, has been deemed unconstitutional by the U.S. Supreme Court. But the battle continues.

Technology plays an increasing role in Homeland Security efforts, spawning a growing U.S.industry for everything from biometrics to cargo screening at ports.

The air travel system remains one of the most high-profile targets for terrorists. This backgrounder examines efforts to improve aviation security since the 9/11 attacks.

The “war on terrorism” is often portrayed as playing out on the streets of Baghdad or in the mountains of Afghanistan. But New York City is another important battleground and could provide lessons fo…