Land and sea expansion. After independence in 1776, the territory of the United States was still limited to 13 states along the Atlantic coast. But Americans are lucky. They have vast and fertile land in the west and south. The United States acquired more than 5 million square kilometers of land from France, Spain and Mexico through purchase and war capture. This westward expansion contributed to one of the most important events in American history: the unification of the domestic market. By the end of 19, the domestic trade of the United States was about 20 times that of foreign trade, even exceeding the sum of foreign trade of all countries in the world. No country in the East or the West is so enviable as the United States. By the end of 19, the focus of population, agriculture and industry in the United States has moved westward in an all-round way, and at the same time, the United States has been pushed from a weak country to the throne of a world economic power, and the total industrial output value has jumped from 1894 to the first in the world. 1890, the "frontier" of the United States disappeared, and there was no more land in North America that could be developed as a frontier area. But Americans have not stopped expanding. At the same time as the strength of the navy jumped, the United States also began the pace of maritime expansion. Hawaii, the Philippines, Guam and Puerto Rico have successively become trophies of the United States, and American control and influence have extended to the central and western Pacific Ocean.

Pioneer of the industrial revolution. 1On September 4th, 882, Edison personally turned on the switch of the world's first commercial power system, and the current flowed rapidly along the wires, illuminating 58 places including Morgan Company in Manhattan financial district of new york. Motivation is one of the decisive forces in the process of national and social development. The power equipment invented by Edison only took 30 years of practice to create achievements equivalent to those of the previous 100 years, which changed the pattern of world power. The invention of electric light and the application of electric power system made the United States take the lead in opening the electric power era and becoming the hometown of electric power industry, thus taking the lead in entering the second industrial revolution. In the competition in the capitalist world, the United States quickly replaced the leading position of Britain and France and walked in the forefront of the world as a leader. It was in the electrical age that the American economy came from behind. 1860, its total industrial output value was less than half of that of Britain. By 1894, the industrial output value of the United States has jumped to the top in the world, twice that of Britain and three times that of France, accounting for nearly one-third of the world's total industrial output value. In the second half of the 20th century, it was the United States that initiated the information revolution, which enabled the United States to lead again and maintain its leading edge. It may be said that whoever initiated the new industrial revolution became the leader. It was by taking the lead in opening the second industrial revolution that the United States was able to surpass Britain and replace European powers as a new world power.

Policy dominates the world order. As early as before the First World War, the economic strength of the United States had far surpassed that of the European powers, but it was the two world wars that really extended the influence of the United States to Europe and even the world. In the war, the strength of great powers such as Britain, France and Germany was greatly weakened, and only the United States became the biggest beneficiary of the war. 19 19, American president Woodrow Wilson landed on the European continent with a plan to deal with post-war problems, trying to dominate the "peace" conference held in Paris. However, other victors rejected Wilson's basic ideas, and America's efforts to build a post-war international order ended in vain. As a result, Americans returned to the American continent and concentrated on their own affairs. Before World War II, the total industrial output value accounted for 38% of the world, more than Britain, France, Germany and Japan combined. Like World War I, in World War II, the United States was not destroyed by the war, but also gained a unique development environment and its strength expanded rapidly.

From 65438 to 0945 after World War II, the United States owned 60% of the total industrial output, one-third of foreign trade and three-quarters of gold reserves in the western world, making it the largest capital exporter and creditor in the world. At the same time, the international financial system centered on the dollar has been established on a global scale. In 1945, the total number of American troops exceeded120,000, making it the maritime hegemon. Hundreds of military bases are distributed all over the world, controlling strategic points far from home, monopolizing atomic bombs and becoming the number one military power. For hundreds of years, the situation centered on Europe has ended, and the focus of world capitalism has shifted to the United States. The United States became the country with the largest expansion after World War II. The farthest area dominated by the former Soviet Union is 960 kilometers away from its border, and the farthest area dominated by the United States is 1 1200 kilometers away from its border. After several generations of painstaking efforts and a very convenient international and domestic environment, less than 200 years after the founding of the People's Republic of China, young America has become the most powerful country in the world.