What is the capital of the U.S.?

The capital of the United States is Washington D.C. because it was established as the nation's capital in 1800, serving as the political center of the federal government. The city was specifically chosen for its location along the Potomac River and was designed to serve as a neutral ground between the northern and southern states. This significance is highlighted by the presence of important government buildings, including the White House and the U.S. Capitol, which symbolize the nation's governance.

Other cities like New York City, Los Angeles, and Chicago are major urban centers in the U.S. but they do not hold the designation of the capital. New York City was the temporary capital before Washington D.C. was established, and while Los Angeles and Chicago are influential city hubs, they do not serve the political functions associated with being the capital.