Fully agree. Trump is a symptom of the American cultural response to this decline, not the source.
USA very much followed the pattern of the Spanish Empire. Found a golden goose that turned their currency into the world standard, and proceeded to import themselves out of self sufficiency.
That being said, on May 26th 2016, I was laughed at by my entire work office for saying that Trump winning the GOP nomination (At that time we all assumed Hillary would win) would be noted by future historians as the beginning of the dissolution of the united states. Trump is a snowball, not snowfall.
And honestly that's what were seeing with California filling the void left from defunded federal agencies like FEMA, FDA, EPA, etc. I honestly predict that the USA will splinter into several factions depending on what states participate.