Why are there so many departments in the US government, Congress, House of Representatives and the Federation?

(1) Congress is the central legislature of the United States, which enjoys legislative power and is not controlled by the United States government. On the contrary, the US Congress has the right to supervise the work of the US government.

(2) The House of Representatives is subordinate to the United States Congress. The United States Congress is divided into the House of Representatives and the Senate. Compared with the Senate, the House of Representatives is more like a subordinate of a superior.

(3) The Federal Bureau of Investigation (hereinafter referred to as the FBI) is subordinate to the U.S. government, and is responsible for investigating some cases in the central and local governments, which is similar to the police department, but nominally the FBI only enjoys the right to investigate and has no law enforcement power.

(4) The Central Intelligence Agency (CIA) is subordinate to the U.S. government and president, and is responsible for collecting domestic and foreign information related to domestic and foreign affairs in the United States, so that senior government officials can make correct decisions. It has both investigation power and law enforcement power. In the 1950s and 1970s, the CIA even intervened in the internal affairs of other countries. Many countries in South America have had coups, with more or less CIA intervention behind them. It is said that the former Cuban leader Castro was assassinated by the CIA more than 300 times.