The goal of interracial marriage bans and legalized segregation was to maintain a subordinate class of citizens based on race. The goal of same-sex marriage bans is to protect traditional marriage, not maintain a subordinate class based on “sexual orientation.” One would be hard-pressed to argue that homosexuals in America are second-class citizens.
Marriage is a legal union and social institution recognized by the states as serving fundamental purposes: providing structure for family formation and rearing children, and acting as a stabilizing influence that benefits the whole society. Changing the definition to include the union of two men and two women opens the door to legalizing increasingly deviant unions. Marriage will cease to have any meaning at all.
For instance, if we extend marriage to same-sex couples, on what grounds can we deny the same to three people? Or 10? Or close relatives? Or adults and children? It makes a mockery of marriage.
Individuals are worthy of equal treatment under the law, regardless of race, but an individual’s lifestyle choices are not.