Have you forgotten that every other country had its infrastructure blown to smithereens during that war?
No, I have not "forgotten" this mythical claim.
What was the manufacturing capacity of France, Germany, UK, Japan, or USSR after everything had been bombed?
Slightly higher than before the war, in most cases.
Much higher in the case of the USSR.
They were fighting a war. That requires massive production of materiel, and rapid repair or replacement of that which is damaged or destroyed. They had also trained the other half of their population to do work traditionally reserved only for men. Europe and Japan boomed in the 1950s, just as the USA did.
I'm surprised you had to even ask, it is such a well known and obvious result of WWII.
It's a popular myth in the USA. I grew up in the UK, so I was never told this nonsense; It would have been obvious that it was nonsense anyway.
It wasn't because they were paying us for protection, it is because we were the only major industrial nation with infrastructure intact. If you wanted manufactured good, it was going to be Made In America.
Except, it wasn't. Most manufactured goods were made in Germany or Japan.
Europe was awash with German and Italian cars, most made in factories that had quickly shifted from building aircraft or tanks.
The UK struggled to compete with Germany, particularly in the 1960s and '70s, because at that time Germany had modern factories built in the '50s and full of new 1950s machinery and equipment, while British industry was still trying to build consumer goods with machines designed and built in the 1920s and '30s.
The countries that had their infrastructur destroyed in WWII suffered in the late '40s and early '50s, but it didn't last.
That's why the torch was passed from the UK to the US. It wasn't because other countries were paying protection money.
Your myths might feel to you like knowledge; They might he fairly internally consistent, and even appear 'obvious'; But they are, nonetheless, myths.