Yeah, but the happy times in the 50s to the 70s had one more factor, that the world was recovering from an insanely destructive world war that left the US unscathed, a unique thing at the time.
China was just coming out of a nation-deciding civil war, in addition to the genocide and war with Japan, Japan had Hiroshima and Nagasaki, Europe was in ruins and was gearing up to holding guns to each otherβs heads for the next 40 years, and Russia was kinda like it is now.
I wasnβt even really talking about the boom after the war, I was talking more about the progressive reforms and things that happened that helped end the great depression which was mostly before the war. The war definitely helped continue that recovery and expand it into what we saw after the war but I think generally people agree the great depression was over in 1939 which was right as the war was starting.