For a starters, I can think that there would be no special treatment for anyone regardless of race, sexual orientation or anything else. No one gets free anything that they don't earn.
No social entitlements for single mothers, unless they are widows, or they work or something like this. Maybe cut their social entitlements if they have more than one child they can't pay for.
No illegal immigrants.
English is the official language.
You're getting downvoted, but that's only because most of us know at least one black, and one Puerto Rican that's pretty decent. Or maybe even excellent.
But you are not entirely wrong. The fact is, racial homogeneity breeds Harmony.