The US began the war as a large country with an incredible industrial base. The US was also largely self-sufficient- that is, it could make enough food and supplies in its own territory that it didn't need to get them from other countries. Once the US got involved in the war, it was able to turn most of those massive industrial resources into war-related resources.
But also, the US was hardly affected directly by the war. US territory was only directly attacked at Pearl Harbor, a couple small Alaskan islands, and a few other very minor incidents (like Japan tried using balloons to drop very small bombs on the West Coast- the plot mostly failed). The US lost thousands of soldiers, sailors and marines, as well as a lot of materiél, but the land of the US was hardly scratched.
Meanwhile, countries in Europe and Asia, but also Africa and the Pacific, were absolutely devastated by the war. Modern European countries that could rival the US, like England, France, Germany and even Russia, bore the brunt of the destruction. They lost not only their industrial capacity, but entire cities were leveled.
So the war ended with the US as being the only major country that was not really directly physically affected by the war, and was able to keep its industrial and economic power. Only Soviet Russia could compete- mainly because, despite being invaded by Germany, Russia is just incredibly huge. As German troops invaded, Russia's leaders finally did something smart and moved a lot of their industrial equipment further east, where the Germans could not easily affect them. Russia also had greater manpower capacity than the US- that is, they have more people, so their armies can be much larger. Lastly, the war ended with Russia in control of most of eastern Europe, and with great influence over communist movements elsewhere (China, Korea, Vietnam, etc).
It was the end of two superpowers, leaving the US as the sole superpower of the world It was the end of two superpowers, leaving the US as the sole superpower of the world
In the World War 2 period there was no one power that could be called "the World Superpower" so the US did not defeat it. At present some call the US "the World Superpower." Whether that is a valid description or not is a matter of opinion, but even if true it is still not possible for the US to defeat itself so the US has never defeated "the World Superpower."
For a brief period of time, the US was alone as a world superpower.
Strongest in the world.
The US was considered a superpower after World War II, when the European powers declined, partly because of the loss of their colonies to independence movements. The war similarly sparked the advance of the Soviet Union to superpower status, and the Maoist takeover did the same for China. Whether the US currently shares superpower status with China is debatable, but China does not yet have an equal international presence. China (and most of Asia) has benefitted substantially from trade with the United States. The beginning of US worldwide influence dates from the Spanish American War, which brought it the Philippines and increased trade in the Pacific.
The US turned into a superpower
US and USSR
The United States emerged from the war as superpower.
it was the strongest economy in the world
After the Cold War, the United States emerged as the world's leading superpower. Even as a superpower, the US cannot enforce all of its policies on the rest of the countries in the world.
It was the end of two superpowers, leaving the US as the sole superpower of the world It was the end of two superpowers, leaving the US as the sole superpower of the world
After World War 2, the US had the strongest economy in the world.
In the World War 2 period there was no one power that could be called "the World Superpower" so the US did not defeat it. At present some call the US "the World Superpower." Whether that is a valid description or not is a matter of opinion, but even if true it is still not possible for the US to defeat itself so the US has never defeated "the World Superpower."
because of us participation and victory in wwii, after the war the us emerged as a superpower and world leader.
World War I affected the US by making it in charge of all other world powers. In other words, the war boasted the country into becoming the world's superpower.
US and USSR
The American economy became the world's strongest.