There is no definitive answer to this question as it depends on a number of factors, including the political and economic situation of a country, the size and population of a country, and the military capabilities of a country. However, some experts believe that the United States has the most powerful military in the world. The United States spends more on its military than any other country in the world, and it has a large number of personnel and sophisticated equipment. The United States also has nuclear weapons, which are considered to be one of the most powerful weapons in existence.