Part of United States ideology is that the country is a peace loving nation. History tells us a different story, particularly when we consider that whites have been at war with the indigenous people of this continent, pretty much continuously since Columbus stumbled upon West Indies in 1492. Some people reckon this war to have ended in the U.S. in 1890, but there were skirmishes after that and if you consider a textbook definition of institutional violence, as the deprivation of opportunity, health care, education, culture, etc., war continues on the reservations to this day.
Even using more conventional definitions of conflict, however, an image of continuous violence emerges. While you might disagree with a reckoning that includes the Cold War as war, those of us who remember any part of it know that we lived under a continuous threat of worldwide nuclear devastation under a policy of mutually assured destruction that led both the United States and the Soviet Union to acquire many more nuclear weapons than either would need to destroy the entire planet. This, too, is a form of sustained violence.
So given all this, just how does the U.S. stack up as a supposedly peace loving country? It is actually not a simple matter to find out all the wars the the nation has been involved in. And a large number of the wars overlap. But Roger Lee has a list, which I plugged into a spreadsheet. And when I put the data through some manipulations, I came up with a grand total of 16 calendar years in which the United States was not at war with someone, somewhere, somehow. The longest of these periods was eight years. We have been at war the entire rest of the time.