E. O. Wilson once said that there are three major philosophies alive in the world today: monotheism, communism, and scientific thought.
Another way of looking at things is that there are two major philosophies alive today: regionalism and globalism. Proponents of the latter are generally accepting of, or even welcome, the elimination/globalization of all cultures, races, economies, and political systems into a global culture, race, and government. Globalism typically comes in two flavors: global Marxism, and global capitalism/democracy/plutocracy.
The presidency of Calvin Coolidge represented regionalism. The U.S. would remain uninvolved in most foreign entanglements, it would accept relatively few immigrants to maintain demographic stability, and no effort was made to mold the rest of the world in the image of the U.S.
However, there were two forces working against regionalism in the U.S.: globalist Marxism and globalist capitalism.
The stated long-term goal of the Marxist movement is global conquest. The first leader of the Soviet Union who did not articulate that goal was Gorbachev. Conquest can come in two forms: military conquest and revolution. Military conquest gained the communists Poland, Czechoslovakia, the Baltic States, North Korea, South Vietnam, and so forth. Revolution gained the communists Russia, China, Cuba, North Vietnam, etc. It was felt that nations like the United States were too strong to be conquered by military conquest, making them good candidates for communist revolution instead.
Before a communist revolution within the United States or Western Europe could occur, it was felt that anything which supported the existing social order would have to be eliminated. On that basis, Marxists and communists have supported attacks on traditional morality, the family, patriotism, the existence of race, Coolidge-style immigration policies, and so on. They have celebrated criminals as heroes and revolutionaries for resisting an evil social order. They have become deeply involved with radical feminism, the drug movement, attacks on Western culture and Western civilization, and anything else which seemed to promise to corrode the existing social order.
At least in a number of areas, the objectives of globalist Marxists coincide with those of globalist capitalists. Marxists favor high immigration as a means of destroying local cultures and the existence of race. Global capitalists see large-scale immigration as a useful tool to lower employees’ wages. Some global capitalists seem to recognize that mixing multiple cultures together creates a cultural vacuum–a vacuum which their multinational corporations can step in and fill. Global Marxists tend to favor increases in the size of government as a mechanism for promoting a Marxist agenda. Global capitalists sometimes favor increases in the size or power of government as a means of restricting their competition, obtaining government handouts for their companies, and so on. The respective agendas of global Marxists and global capitalists for Western nations sometimes blur together.
Among modern Western nations, globalism, not regionalism, is clearly in ascendancy. The 19th century person most closely associated with globalism–or at least with its Marxist half–was of course Karl Marx himself. While Western elites would still be making a strong push for globalism even if Marx had not lived, Marx’s philosophy and eponymous political movement have played a major role in pushing it forward.