The Federal Government
The federal government in Washington is the national government of the United States. The United States government is the largest bureaucracy in the world, and the largest employer in the nation. While the federal government is centered in Washington, D.C., most of its employees actually do not work in Washington, but elsewhere around the nation and even around the globe--this fact alone suggests the U.S. government's extraordinary size, reach, and influence.
The Constitution reserves some of the tasks of government exclusively to the federal government, such as conducting diplomacy, and raising and commanding the armed forces of the United States (states do have militia or National Guard units). The federal government also has some specific powers over the states: most importantly, Congress has the authority to regulate commerce between the states. This power places the federal government in a superior position over the states. Congress also has the power to raise taxes, as well as to borrow money. It has the authority to raise armies and navies and to declare war. The president conducts foreign policy and is commander-in-chief of the military. (Congress, which has the power to declare war, has lost some power to the president in this regard.) The Supreme Court is the highest court of appeal when legal questions arise concerning the interpretation of the U.S. Constitution.