There has never really been capitalism without the US. The US is the global center of capitalism
I'm just going to nitpick on this. While it's really irrelevant to your point, Capitalism began in earnest in Europe with the industrial revolution, and the while the United States followed this trend closely and engaged in a litany of its own colonial projects, I wouldn't consider it to be the vanguard of Capitalism as an economic system at this time. Up until around World War Two, you could argue that England remained the epicenter of the financial system. This is when things truly shifted and the US took the reigns on a global scale.
In the time since then, the US has consistently remained the center of the imperial core - particularly throughout the entirety Capitalism's phase of global imperialism, which Lenin and Luxemburg predicted with startling accuracy.
I'm just going to nitpick on this. While it's really irrelevant to your point, Capitalism began in earnest in Europe with the industrial revolution, and the while the United States followed this trend closely and engaged in a litany of its own colonial projects, I wouldn't consider it to be the vanguard of Capitalism as an economic system at this time. Up until around World War Two, you could argue that England remained the epicenter of the financial system. This is when things truly shifted and the US took the reigns on a global scale.
In the time since then, the US has consistently remained the center of the imperial core - particularly throughout the entirety Capitalism's phase of global imperialism, which Lenin and Luxemburg predicted with startling accuracy.