America was blessed with vast resources and opportunities and distance from the warring of Europe. America came to inherit the global resource hegemony of Britain post WW2 and with that global USD hegemony over trade payments via SWIFT. Today USAs wealth and power is based on its domination and control over global institutions, protocols and trade with the worlds largest military to back it up. But USA today does not enjoy the massive advantage it had post WW2 in manufacturing. Today China enjoys that position. Thus it is China that buys the commodities from commodity producers and sells manufactured goods to almost everyone. China thus controls the markets in many commodities and manufactured goods. Few if any nations today can afford to cease trading with China because its economy is so dominant in both commodities and manufactured goods. China can provide Russia and Iran with almost all the manufactured goods they need at the best prices and can buy all of their oil and gas exports. USA does not have such a comprehensive and broad mercantile dominance and is thus vulnerable if/when it loses its control over trade payments/banking...and this is already happening - USA is losing its monopoly over trade payments because now China can offer a broad and effective Yuan denominated alternative.