If you want to know the details of one section of the US economy that is booming, you need to read this report. All empires require the use of force to rule, and with 30 percent of the global market, the US governing class together with other governing sections of the Empire are determined to maintain their hegemony over most of the world.
...geographical trivialities have never been a concern to imperialists who believe that the world belongs to them and it was a mere accident of history that all the resources exist outside of the empire’s home country. Therefore, with such a rationalization, the United States – and the West more broadly – have a “right” to “defend” themselves (and their economic and political interests) everywhere in the world, and against everyone in the world. Any other nation which poses a challenge to Western domination of the world and its resources is thus a “threat” to whichever region it belongs, as well as to U.S. “national security.”While there is much discussion of restricting the sale of arms within the US mostly by liberal-left activist groups who have essentially made the practice of non-violence into a religion, there seems to be no debate about the lucrative business of supplying the worst dictatorships, terrorist groups, and drug dealers throughout the world with weapons.
See also this article entitled "Mexico: study says arms smuggling keeps US dealers in business".