There is a short answer, a long answer, and a theoretical answer to this question. I'll try to keep it short, sweet, and include a little bit of everything.

The quick and dirty answer is that the United States realized its fully massive industrial potential after the Second World War (or even after First World War, but just didn't want to deal with it, according to some authors like Charles Kindleberger). Why? The United States is a massive country, but unlike other large countries, like China and Russia (more on that later) the States' legal system is based on the British one; and as such is inductive to a business-friendly political and legal system. The United States even has a social structure similar to the British one: a relatively isolated terretory with low population density where scarce workers command high wages, increasing ability to consume and standards of living (of course, the actual availability of goods and services in the sparsely populated United States has quality-of-life implications, but that doesn't impact the potential for consumption, just the ability to use that potential).

So you see, if the United States was more successful than other large states because its legal system was based on the first European country to industrialize, and the United States in turn supplanted the European powers which begat it thanks to its massive terretory, seemingly limitless natural resources, and the consequential ability to scale upwards (a positive feedback loop, of sorts. Which impacted first? Tough to say. See Scale and Scope, by Alfred Chandler). The highly competitive European powers had certainly been the first to industrialize, but their smaller size meant they rapidly capped off their growth potential and, in the interest of safeguarding the national interest, began stepping on each others toes.

Some might interpret my opening line by thinking that I'm arguing the United States could achieve its potential because European powers pulverized themselves over the course of two world wars. But that's not seeing the forest for the trees; the United States certainly realized it was a world power after the First World War, and became a superpower after the Second World War, but the wars only really steered the States' towards realizing the extent of what was achievable thanks to the ability to the massive resources and scale of the country.

What sustained that ability to exploit the country's advantages in the ability to project power was the Cold War. Following the Second World War, there was a tangible worry that a third conflict in Europe was imminent: the Soviet Union, although battered by war and internal upheaval, was the only country that could scale its resources and industrial production to the extent that the United States could, and it was a country ruled by a ruthless dictatorship not all that different from the one defeated in Germany.

Now there's a whole conversation to be had on what really caused the Cold War; my take is that both countries were extremely reluctant to partake in the whole ordeal (the United States wanted to avoid another European war; the Soviet Union was only really interested in securing its immediate borders) but what is certain is that in the immediate aftermath of the Second World War, the Soviet Union had won a costly victory only to find a superpower deployed at its doorstep. Who wouldn't be terrified? The United States, for its part, saw an authoritarian power consolidate its hold over the eastern half of a continent that had just seen massive conflicts; the stage was set self-perpetuating cycle of suspicion leading to massive arms buildup. No other country in history developed the capacity to project power the way the United States and the Soviet Union did (Europe tried, but couldn't get its affairs in order. I wrote about the early drive for European Integration here which you might be interested in).