It wasn't much like China at all in my opinion. China heavily directs its economy, subsidising industries and players it thinks are critical to compete. Their companies aren't simply "given room". The US had protectionist tariffs and gave land to railroads and stuff, but nothing like the kind of industrial policy in modern China. Nor did the US really stay out of wars, although Civil War aside it mostly avoided bad entanglements where it couldn't win or winning cost a lot.