Start with pot. Last November voters in the states of Colorado and Washington voted to legalize marijuana, by a 55 to 45 percent margin in Colorado (more than Barack Obama's margin in the state) and by 56 to 44 percent in Washington.
In contrast, California voters rejected legalization 53 to 47 percent in 2010. These results and poll data suggest a general movement toward legal marijuana.
State legislatures in Denver and Olympia have been grappling with regulatory legislation amid uncertainty over whether federal law -- and federal law enforcers -- override their state laws.
But marijuana has already become effectively legal in many of the states that have reduced penalties for possession of small amounts or have legalized medical marijuana. You can easily find addresses and phone numbers of dispensaries on the Web.
Same-sex marriage, rejected in statewide votes between 1998 and 2008 and most recently in North Carolina in May 2012, was approved by voters in Maine and Maryland in November 2012, and voters then rejected a ban on it in Minnesota.
Since then, legislators in Delaware, Minnesota and Rhode Island have voted to legalize same-sex marriage. A dozen states and the District of Columbia now have similar laws that would have been unthinkable two decades ago.
I have yet to see signs of political backlash. Polls show that support for same-sex marriage is well nigh universal among young Americans, but it has also been rising among their elders.
To some it may seem odd to yoke together marijuana and gay rights, generally thought of as causes of the left, with gun rights, supported more by the political right. Yet in all three cases Americans have been moving toward greater liberty for the individual.
One landmark was the first law, passed in Florida in 1987, allowing ordinary citizens to carry concealed weapons. Many, including me, thought that the result would be frequent shootouts in the streets.
That hasn't happened. It turns out that almost all ordinary citizens handle guns with appropriate restraint, as they do with the other potential deadly weapon people encounter every day, the automobile.
Concealed-carry laws have spread to 40 states, with few ill effects. Politicians who opposed them initially, like former Michigan Gov. Jennifer Granholm, have not sought their repeal.