The problem is too many resources devoted to skimming the cream at the top of the economy, decade after decade of ill-advised military waste, too much easy money in finance, too gullible of a pacified electorate ready and willing to vote against their interests at the siren song of two parties who claim to represent their values, but spend 95% of their time fundraising and earning it from the private interests who expect their ear.
If as a country we got back to the basics of hard work and innovation and spent less time hand-wringing over our safety and global dominance, and making sure that the GDP is growing at all costs, then I think we'd be well positioned for the coming centuries of increased parity between countries. Insistence that we have to maintain the post-WWII imbalance that America enjoyed due entirely to a accidental confluence of events is foolhardy and will lead to bad decisions.