Former three-time Republican presidential candidate Alan Keyes, who has an affinity for conspiracy theories, apparently believes gay marriage is sort of like owning slaves.

Keyes, an African-American, wrote on the conspiracy-minded website World Net Daily that "granting homosexuals the right to marry is like granting plantation owners the right to own slaves."

"Government doesn't endow people with the ability to procreate the species. The Creator takes care of that... The DOMA simply makes more explicit the government's obligation to secure the Creator-endowed unalienable rights of the natural family. This obligation precludes government from fabricating other rights that impair them," he explained.

Keyes proceeded to offer a long-winded explanation for why same-sex marriage is immoral and an affront to American values.

The piece came after the Obama administration announced that it would no longer uphold the 1996 Defense of Marriage Act -- which defines marriage as a union between a man and a woman -- on the grounds that part of it is unconstitutional.

Keyes hosts a radio program called The Alan Keyes Show: America's Wake-Up Call. He served as a diplomat during the Reagan administration.