The National Organization for Marriage (NOM) have been the primary opponents of state-level marriage equality legislation, including Proposition 8 in California and Question 1 in Maine. And this summer, they've been on tour denouncing same-sex marriage around the country. According spokesman Brian Brown on Twitter,

“It is 1972 for marriage. This is the same as the time as before Roe v. Wade. . . . What if William Wilberforce listened to those telling him not to bring his religion into the public square?"

William Wilberforce was a British Member of Parliment in the 19th century who was almost single-handedly responsible for ending slavery in the British empire, and is today lauded as one of the most famous abolitionists in the world. He was also a devout Christian, which is the religion Brown references. But by comparing Wilberforce's public campaign against slavery to NOM's public campaign against marriage equality, they are equating the systematic sale and enslavement of an entire continent of people with the extension of the right to marry whom they choose to all Americans.

This comparison is offensive on more levels than a video game convention in a skyscraper has. It's offensive to LGBT people and marriage equality advocates because it equates them with slave traders. It's offensive to modern-day abolitionists and human rights adovacates, because it belittles the horrific abuses they fight by equating them with a generally positive social instiution. And it's offensive to people who think and use common sense, because same-sex marriage is no more comparable to the slave trade than apples are to a Ford Pinto or outerspace.