If you look at oil prices, the Iran-US-Israel-Saudi war is now everyone's problem globally, whether they're part of the hegemon or not.

It's very difficult to disconnect from the problems of the world when your fuel is imported (+) from the middle east and your chips are imported from the Far east. Trying to be an autarky is .. well, the US might be able to do it, but it will be fearsomely expensive.

(+) US is currently a net exporter of oil/petroleum products, but that is a recent development and subject to change