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When did America start to decline?
(hexbear.net)
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? 
I think the UK is a little different than where America is heading because their colony inherited all their power. You could easily view America as an extension of the British Empire. I wouldn't be surprised if its seen that way in the long view of history. I don't think China is going to be quite as chummy and enabling of America as is, the way the Americans were with the British.