It's very obvious that 
is circling the drain now, but clearly this didn't just happen in a vacuum. It must've started crumbling at some point... but when?
Some people might say it started after 9/11, others might say it goes back to the Raegan administration. A few might even say it started after losing the Vietnam War, or when they went off the gold standard. Or maybe even earlier...
What do you think? 
1492 downhill ever since
if you want to talk living standards its always been phenomenally unequally distributed, but the 70s is when the small amount of progress toward equality started being reversed.
the objectively correct answer. the genocide on turtle island started then and it's been worse than that for one reason or another globally since.