Expansion has long been a theme in American history, ever since its creation as a country, with the idea of American Exceptionalism, or that America is unique among the world’s nations. This also ties to the idea of Manifest Destiny, which was a commonly held belief by Americans in the 19th century that the nation and its people were destined to expand across North America, and spread our nation’s beliefs and ideals across new lands. Before the Civil War however, the US was almost entirely an agrarian nation, in the vision of Jefferson. This lead to much of the direct and vast territorial expansion of the continental United States, as rural farmers needed land to work and the emerging US economy needed raw resources beyond those in the East coast.
This period of rapid continental expansion would come to an end however with the Civil War, as the US reached from sea to sea. Industrialization also led to less need for land and more need for development, causing the to US begin to consolidate and encourage settling of the vast lands in the west during the second half of the 19th Century. Before the Civil War the US was a more decentralized country, with regional differences, especially north and south, preventing a more unified national identity. After the war and Reconstruction though, the US emerged a more centralised country, with the federal government supreme over state and local governments. As a result, the government began to further push for the removal of lands previously held by Native Americans, in order to be used by businesses, railroads, and other settlers, and “conquer the West,” from native tribes. With the completion of the first transcontinental railroad in 1869, American industry was now able to access the interior of the country, and open the vast Midwest to settlement.
In the 1880s, as memories of the Civil War began to disappear, the US had a rejuvenated sense of national identity, and a rapidly expanding economy with the onset of the Gilded Age. This would lead many Americans to advocate a new sort of manifest destiny, that not only concerned America, but the world as well. The US began to seek outside markets to its burgeoning economy, and would support this to the public with ideas of fulfilling a greater duty to the world, and spreading American values to all people. With the presidency of Benjamin Harrison, who began to advocate for an expanded navy, the US would now be able to back the Monroe Doctrine, which had previously been ignored by most European nations. The naval build up and urge to fight would directly lead to the Spanish-American War in 1898, which had the US portray itself as a liberator to both American nations, and other Pacific islands, such as the Philippines. With the direct occupation afterwards as the US won the war, conflicts such as the Philippine-American War, which lasted from 1899-1902, showed America’s willingness to fight for its overseas expansion, even as it championed freedom and liberty as rallying calls. The Boxer Rebellion was another example of these more imperialist policies, with the US joining other empires to secure private interests in China. Often times, these issues were interconnected, with the US benefiting from both spreading its values and its markets, yet struggling to maintain its image of democracy as it drew closer to other European nations in imperialist policies.
During the early 20th century the US would also continue fighting against insurrection in the occupied Philippines, which would continue until World War II. America would also seek to insure economic interests abroad, through various military interventions. Examples of this are prevalent with the Banana Wars, a series of interventions and occupations throughout Central American and Caribbean nations. These conflicts occured from 1898, with the end of the Spanish-American War, to 1934, when President Roosevelt would seek more peaceful relations with fellow American nations through the Good Neighbor Policy.
As World War I approached, the US sought to differentiate itself from the other European powers, a majority of whom were empires of some form. Because of this, it began to shift from a more aggressive policy of directly occupying territory to instead supporting local governments that were favorable to US interests, such as in Nicaragua, Cuba, and the Dominican Republic. Most importantly though, WWI permanently established America’s presence in the world, shifting it from a regional power that occasionally intervened in issues outside the Americas, to one of the “Great Powers” at the negotiating table at the war’s conclusion. Most other countries also experienced extensive damage to their economies and population, in contrast to the US which would emerge an even more energized industrial powerhouse, eager to expand its markets abroad. Throughout the interwar period, most nations, including America, would attempt to have a more peaceful, non interventionist policies, which would only last until WWII.
As WWII began, and especially as the Cold War started after it, the US began to ramp up its presence in international affairs. As the US became the foremost democratic, capitalist country, in economy and military, in its battle against the Soviet Union. The US would economically support the war torn nations of Europe after WWII with the Marshall Plan, in order to create strong allies against communism. America would continue to finance and support governments that would combat the spread of communism, through the establishment of the Truman Doctrine as the official foreign policy. Conflicts would range from Eastern Europe, to Asia, to the Americas, and Africa, a truly global conflict. This would also begin the establishment of US military bases worldwide, that would leave an American presence worldwide to this day.
In 1991, with the dissolution of the Soviet Union, it would seem that the US was the victor of the 45 year long conflict between democracy and communism. The US would have to shift its view again, from combating communism, to securing its interests worldwide in the new post-Cold War era. America would stage several interventions, mostly in the Middle East and Africa, to stabilize the area. The reasons for this would be both the geopolitical importance of the region and the economic importance, stemming from the vast oil reserves. Many contemporary scholars now argue that the US has continued its imperialist policies from the past, only now more covert, and fundamentally different from the direct territorial expansion of the early America.