Yes, the USa could be such a shining example of implementing the dream. I remember singing, in grammar school, so many songs that touched on this theme. It actually convinced me, for a time, that USa really wanted that dream to become reality. G.d Bless America, America the Beautiful. I especially remember the line I thought, for many years, was a guide in American politics: "Thine alabaster cites gleam, undimmed by human tears."
Yes the singing of those 'patriotic' songs in schools was indoctrination... pre-conditioning kids to toe the line and not question 'patriotic' thinking as adults. So glad I didn't have to put up with that sort of crap when I was in school during the 60's... I hated being told how to think even as a kid.
We were so close, back in the 60's to winning the war on poverty, and focusing on exploration. Humanities were not a discipline looked down upon because it did so little to equip college students for careers in business. Yes, the war machine has always been there. But, it once coexisted well with the American dream. Now the war machine is consuming it all. No real money left for human needs, fulfillment, etc. The dream is becoming, for many people, a nightmare. They are destroying the "US" in USa.
The same thing is happening here in Australia, but for different reasons. The great Australian dream of owning one's family home is all but a fairy tale for most... unless both parents work 12 hours a day while their kids are in care facilities or left to their own devices, as is too often the case and juvenile crime spirals out of control. We have heartless bankers, greedy real estate agents AND politicians to thank for this, as housing property values also spiral out of control.