This is the 40th anniversary of the great Supreme Court decision, Loving v. Virginia, which struck down state laws against racially mixed marriage.
The Court made three arguments against the Virginia statute:
1) State marriage laws must comply with federal constitutional norms;
2) The statute violated the Equal Protection Clause of the 14th Amendment because it only prohibited mixed marriages involving white people;
3) The Due Process protection of the Constitution means that the state can only violate a basic right if state has a compelling interest in doing so. Keeping the races separate was not, the Court ruled, something Virginia was compelled to do in the basic institution of marriage.
The Loving decision was necessary -- but dangerous.
As a centrist, I welcome the federalist principle that states should make laws suited to the custom and culture of their distinctive people. This is why the federal takeover of any area of state law is dangerous.
On the other hand, I have long thought that anti-black racism is the original sin of America, and it has introduced more misery in our practice and more irrationality in our law than other mistake we ever made. If we had not had whole states that embedded anti-black racism deep in their laws, even their constitutions, we would not have had a civil war, and we would not have needed to hugely expand federal power. This is why Loving v. Virginia was necessary.