Adoption of the UN Charter and the Universal Declaration of Human Rights created a new international norm prohibiting racial discrimination. That anti-discrimination norm had been a part of the paper Constitution in the United States since adoption of the Fourteenth Amendment. However, it did not become a part of the living Constitution until the Fourteenth Amendment was subjected to the magnetic pull of international human rights law. Adoption of the Charter sparked a chain of events culminating in the Supreme Court decision in Brown v. Board of Education, which heralded the end of apartheid in the United States. Many Americans think that modern anti-discrimination law was a U.S. invention that we exported to the rest of the world. In fact, U.S. anti-discrimination law is properly understood as an outgrowth of the creation of modern international human rights law.
David Sloss, How International Law Transformed the U.S. Constitution, 37 Human Rights Quarterly __ (2015).