The United States holds a portion of the world's wealth.
United States . The United States is a highly developed country , with the world 's largest economy by nominal GDP and second-largest economy by PPP . Though its population is only 4.3 % of the world total , Americans hold nearly 40 % of the total wealth in the world . Accounting for approximately a quarter of global GDP and a third of global military spending , the United States is the world 's foremost economic and military power .