The opposite is separate, split, or disassemble.
The United States of America is the opposite of the Confederacy.
United.
parted
Untied
Boise.
Antonyms are united, blended; there may be others.
The country that is exactly opposite the United States on the globe is Australia. If you were to draw a line from the center of the Earth through the United States, it would come out on the other side in Australia.
The opposite may be "useless." Context opposites may be unsuitable, or worthless, or unhelpful.
china maybe or japan???
The opposite of kimono could be western clothing or attire, such as shirts, pants, and suits commonly worn in countries like the United States and Europe.
The country that is on the opposite side of the United States, specifically the continental United States, is typically considered to be Madagascar. This is based on the concept of antipodes, which are points on the Earth's surface that are diametrically opposite to each other. Depending on the specific location in the U.S., other regions in the Indian Ocean or parts of southern Africa may also be antipodal.