We're all riding on the shoulders of giants. The men who designed the postwar world were remarkably prescient in their engineering of affairs to benefit the United States.
The US has another decade or two of riding that wave until things get hairy.
Have you read "The Accidental Superpower"? Highly recommended.
It covers the demography, geology and geography that guarantees the USA will continue to be the predominant power for the next 25 years, if not longer.
Not sure I buy all his arguments, but definitely worth a read.
The problem is the can-do, hardcore engineering types (particularly those without college training) are gone and supplanted by layers of bureaucrats and bean counters.
The US has another decade or two of riding that wave until things get hairy.