The American Republic is, by design, capable of producing greater good for its citizens.
Combined with its wealth, resources and and level of education it is capable of maintaining a position of world leadership by merit rather than force.
These two statements above address potential. Something has gone very wrong in the last few decades and in the last decade particularly.
America's current politcal system produces laws and policies that, for the most part, contradict the will and best interests of its citizens. In the process it has adopted policies regarding the world, its resources and its progress that are at once self-defeating, counter-productive and thoroughly unworthy of emulation.