In 1945, the United States was the only industrialized country not devastated by World War II. While the country already had a long colonial legacy dating back to the Monroe Doctrine of 1823, this newfound global dominance meant that the United States. could effectively take control over much of the world in alliance with the dominant colonial powers, England and France, that were very much in decline.
Some of the most disastrous U.S. military projects during this period include those in Greece, Italy, Cambodia, and the Democratic Republic of the Congo, where the U.S.-backed assassination of the democratically elected Prime Minister Patrice Lumumba plunged the country into a spiral of violence that continues even today.
In addition to the obvious analysis of nearly all U.S. military interventions - namely that they serve to maintain political and economic control of the region in which they take place - there are a couple of points of particular interest around the current round of U.S. military interventions in Iraq, Afghanistan and elsewhere. The first is that all pretense of adhering to the international rule of law and even national rule of law has been set aside. From unconstitutional wire tapping of phone lines without a warrant, to the clear evidence of war crimes at places like Bagram, Abu Ghraib and Guantanamo Bay, the Bush administration has not even attempted to adhere to the law in these colonial adventures.
The second is that some of the worst elements of internal U.S. colonialism and racism, which have their roots in U.S. history of slavery and genocide of Native Americans, are being used internationally. Some of the worst abuses in places like Abu Ghraib have their origins in the prison industrial complex here in the United States.
The third feature of the current "war on terror" can be found in that term itself: it is justified in the name of some imminent threat that could at any moment threaten our lives. This particular aspect is not unique to the "war on terror"; the Cold War, World War II, even smaller interventions such as the Vietnam War have seen a demonizing of the enemy in order to perpetuate the crimes of the United States.
Of course, it's helpful to have enemies who are easy to demonize, and few fit the bill as well as Osama bin Laden and the type of ultra conservative Wahabi Islam that he adheres to. But if the current U.S. government were really serious about curbing that threat (instead of just building up U.S. power in East and South Asia), a war would be the last thing they would think of. Instead, there would be meaningful attempts to reach out to the base from which some of these right wing political organizations draw. Such a dialogue would meaningfully address the substantive grievances of the Arab world, which include the ongoing occupation of Palestine and the chronic poverty of much of the populations, and would probably result in the United States having less influence in the Middle East, not more. And of course, police actions against those who have committed international crimes would also be part of a sane attempt to address global terrorism.