My choice for the personification of the US would be that great American idol, Elvis Presley, circa 1975: once a great talent but utterly spent, drug raddled, corrupted by business men, and rehashing old glories. His grotesque end you couldn`t make up.
Every country has its time in the sun.
I take the point about the US blundering around the world righting supposed 'wrongs' and just assuming everyone will agree with it and then shocked when they don`t. The US` dominance is coming to an end, both for domestic decline, and an ignorance of the better, faster moving rest of the world.
US 'Exceptionalism' has blinded the country to its many failings, and without acknowledging them it cannot make any progress.
In some ways the last few centuries have been an aberration. The world is returning to its natural order, with China dominant. For far longer than the US, China has thought of itself as the centre of civilization, overflowing with confidence, and destined to decide things.
Coming from an older country, the historical pattern is clear.