The US already has interests all over the world, and China is barely emerging as a world power. They will consider it fair for their influence to grow, and we will see it growing at the expense of ours. China's interests in Africa, its win/win deals with African nations that need industrial know-how and have raw materials to feed Chinese growth, already made the news here in the U.S., if only for a little while. Chinese culture and American culture are different, and as we come into competition for international influence, clever xenophobes on each side will attempt to frame the competition as a showdown between good and evil. Add to that the machinations of people and corporations whose financial interests are at stake, and you have powerful forces pushing for war. It seems naive to think that we won't go to war with China, to hope that we are the first generation that can avoid war under these circumstances.
Then again, it is each generation's duty to hope to rise above the last. I hope that friendly attitudes and cosmopolitan cynicism can combine to keep conflict from flaring up, and to snuff out any little conflagrations that spring up instead of escalating them out of pride and fear. But inevitably we must plan for the opposite contingency. At the very least we must plan for mistrust and tension, and therefore, at the very least we cannot depend on a weapon that is indistinguishable from a first strike. The only reason to develop it is for research purposes.
P.S. Oh, man, isn't it a tempting idea to snuff out your main creditor? Nobody in the Congress has a more realistic plan for getting rid of the national debt.