Make America Great Again is clearly referring to the long turn of the 20thC — my area of expertise as a historian. Things that happened during this period: Jim Crow laws Eugenics Economic boom & bust cycles Immigration restrictions The rise & fall & rise again of the KKK Huge income inequality

Someone needs to ask him how long it takes to "make America great again ", since it was Reagan's slogan, too.

But we did get a huge labor movement, an early civil rights movement, and a push for women's rights, so we have that (with the understanding that those movements had their own issues)