The United States should most certainly keep increasing their foreign arms sales because of the two fold benefit. The United States is making a large fortune of money by doing this, and by only selling to those supporting the US causes, they can help secure victories in wars that will be advantageous to them.
The United States is a nation of hypocrisy; pledging for global nonviolence whilst perpetuating an arms race in developing nations. This traces back to at least the 1950s, where the CIA installed pro-American governments in nations susceptible to Communist influence, and it surged again in the 1980s, when the Reagan administration backed blatantly militant terror groups like the Contras. Not coincidentally, these were two of the most prosperous economic periods in American history. We long ago decided that people can suffer immeasurably on the other side of the world as long as our gas costs a bit less.
When the US government sells to a foreign power, the US is left with no reliable safeguards or guarantees that said arms would not, through deliberate act or theft, end up in the hand of terrorists groups or enemy nations. By continuing, much less increasing, foreign arm sales, the US government continues a practice that weakens national defenses and puts Americans lives in harm's way.
The US should not keep increasing their foreign arms sales. We have seen over the years that these arms end up in the wrong hands. The intention is always good, but it never works out as planned. Rather than having this happen, the US should not increase its foreign arms sales.