Credit: Thomas Hawk / Foter.com / CC BY-NCCredit: Thomas Hawk / Foter.com / CC BY-NCNo matter how the U.S. Supreme Court rules in the two gay marriage cases it will hear this spring, writes Jacob Sullum, polling data suggest it is only a matter of time before legal recognition of same-sex unions is the norm throughout the country. Something similar is happening with marijuana, which became legal in Colorado and Washington in December. With both pot and gay marriage, Sullum observes, familiarity is breeding tolerance.