Second, the two versions of the National Missile Defense system are enormous. The Republican version is a state-based system, which not only destroys or spoils the 1972 ABM treaty, but additionally affects relations with China. Pushing China to overemphasize its military capacity and increase its military technology isn't exactly safe. The Democrat's version is launch-based, and leaves open a capacity to tend to the Russians regarding the ABM treaty, which is not yet safe, but still this version is less threatening. You are a very powerful and very big country, but you are not quite alone on the planet.
Trade is very important, too.
Besides, my information is not sufficiently up to date. Another main problem is the problem with multinational corporations. There has been a surprising, but necessary, condemnation of the United States by the World Trade Organization. Any candidate that speaks about that will lose votes in the United States, so let's keep quiet about that. The Americans speak of Europe as if we are at the end of our integrating process.