It can be surely believed that overall military investment is highly profitable for the United States.
The profit comes not only from the resources directly captured but from "soft power" that is based on the US military potential. By conducting such wars they show that they can easily overthrow any government which policy they do not like very much and that no costs can stop them.
This is a very clear message to any other countries and governments which forces them to conduct pro-US policy such as implementing US-imposed legislation, conducting privatization and keeping their money in US banks.