How did US Moved from economic collapse to economic supremacy?

If you mean from the Great Depression to its state of "economic supremacy" from the late forties onwards, the answer is World War Two. WWII did a number of things for the US's economy--one, it stimulated consumerism for the first time in at least a decade by providing millions of jobs. Jobs in the factory that required little to no skill and that even women could work. And when people had jobs, people bought things, and so companies once again had a reason to begin producing largely--the revenue from these renewed sales and the simple, reinstated circulation of cash in the economy created a flow that could have even by itself renewed the economy. But in addition to this internal repair, diplomacy also played a significant role in the revamp of the nation's economic standings. Since the US upheld a very loose policy of neutrality at the beginning of the War, it was possible for FDR to instigate exchanges such as "cash and carry" and "lend-lease" which put the receiving countries into a considerable amount of debt to the US. After the war was over, these countries had to repay their debt, and even if they didn't, this meant that the US had control over them. Even though FDR's New Deals were great efforts, his instigation of Keynesian economics may have stimulated the economy, but they actually put the US into more debt than it ever had been in before. While these Deals helped, it was really World War II that renewed the economy and put the US in its position of "economic supremacy."