The FBI and the CIA are separated from the Department of Homeland Security, but with the beginning of the Cold War, in order to give full play to their respective responsibilities, the FBI and the CIA set up an independent agency. In a sense, the Department of Homeland Security and the police are the same, but the things they manage are quite different.

Extended data:

The main responsibility of the Department of Homeland Security is to defend homeland security and related affairs, so that the United States can respond to the threat of terrorist attacks more harmoniously and effectively. This department is mainly responsible for four aspects of work:

1. Strengthen the safety of air and land traffic and prevent terrorists from entering the United States;

Second, improve the ability of the United States to respond to emergencies;

Third, prevent the United States from being attacked by chemical, biological and nuclear terrorism;

Fourth, defend the key infrastructure of the United States and summarize and analyze the information from the Federal Bureau of Investigation, the Central Intelligence Agency and other departments.