It's an appeal to restore the country to some form of nostalgic view of it.
https://www.npr.org/2016/06/07/481137357/the-fractured-repub...
The fact that Americans are politically divided is self-evident from recent elections. But just how we are divided and why it's proved so hard to get past our differences are questions that admit to many answers. And here's an interesting one from the conservative political theorist Yuval Levin. He says, American liberals and conservatives are both inspired by nostalgia from mid-20th-century America, and they are mired in hopeless efforts to go back rather than focus on the future.
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The striking thing about the baby boomer's cultural dominance over our country for so long is that we view our own past through their eyes. Our idea of the '50s is this kind of simplistic, childish notion of simple families and everything is possible. We see the '60s as a teenager - idealistic, rebellious. In the '70s, we're somewhat maturing, becoming a little cynical. By the '80s we're settled down. In the '90s everything is great. And now, in this century, it seems like we might be over the hill as a country.