Gay marriage is driving some social conservatives crazy. By “crazy”, I don’t mean opposition to gay marriage as such, but stubborn, even willful refusal to understand why gay marriage has gained so much support, so quickly. Rather than acknowledging the reality of the situation, victims of gay marriage derangement syndrome just make stuff up.

A majority of Americans now approve of gay marriage for two fairly simple reasons. First, most Americans understand marriage as symbolic affirmation of a dissolvable commitment between consenting adults for purposes of emotional gratification. Second, an increasing number of Americans have come to know gay people in their own lives as beloved relatives, respected colleagues, or honored authorities rather than icons of flamboyance or specters of perversion. If you understand marriage in this sense, which has been socially dominant for decades, there is no plausible argument for denying it to gay individuals one loves and respects. As Rob Portman has discovered, the rest is reasoning from the particular to the general.

Opposition to gay marriage isn’t crazy because there are serious reasons to favor a more substantive understanding of the marital union as a lifelong partnership for the begetting and rearing children. On the basis of such a “thick” conception, it is possible to justify the exclusion of otherwise upstanding people. As I argued in a previous post on natural law, however, there’s little hope of convincing a majority of Americans to give up easy divorce and, above all, technologies of reproductive control. These practices, which were embraced by heterosexuals long before anyone had heard of Adam and Steve, are the real threats to “traditional marriage”.

Christopher Caldwell is the latest conservative to succumb to GMDS. In a review of Michael Klarman’s From the Closet to the Altar: Courts, Backlash, and the Struggle for Same-Sex Marriage for the Claremont Review of Books, Caldwell argues that the recent wave of support for gay marriage cannot be understood as a predictable, if not predetermined, development from Americans’ existing beliefs and experiences. Instead, he suggests, it is the result of an unprecedented campaign of unjudicial usurpation and cultural intimidation. Caldwell concludes by citing Klarman’s own evidence that gay marriage has passed a tipping point:

In a decade, gay marriage has gone from joke to dogma. It is certainly worth asking why, if this is a liberation movement, it should be happening now, in an age not otherwise gaining a reputation as freedom’s heyday. Since 2009, if Klarman’s estimates are correct, support for gay marriage has been increasing by 4 points a year. Public opinion does not change this fast in free societies. Either opinion is not changing as fast as it appears to be, or society is not as free.

As Edmund Burke might say: not so fast. According to a Gallup poll, approval for gay marriage rose from 27 percent in 1996, the first year they polled the issue, to 53 percent in 2011. Although not as steep as the trendline over the last few years, that’s still a dramatic increase of 26 percent over a decade and half. But that does not suggest that the change be attributed to fraud or coercion. In fact, it is fairly consistent with shifts on other controversial issues.

Consider interracial marriage, which is the most obvious although in some ways superficial parallel. According to Gallup, in 1972 29 percent of Americans approved of unions between blacks and whites, which is similar to support for gay marriage in 1996. What did they think think after a comparable period of time had elapsed? In 1991 (Gallup also polled the question in 1978 and 1983), 48 percent of Americans approved of interracial marriage.

Over the course of 15 years, approval for gay marriage rose 26 percent. Approval for interracial marriage, on the other hand, rose 17 percent over 19 years. Support for gay marriage, then, has increased notably quickly. But it’s not the kind of off-the-charts increase that requires a conspiratorial explanation.

But maybe interracial marriage is a bad comparison. So consider polling on another controversial issue: marijuana. In 1995, 28 percent of Americans believed marijuana should be legal–just 1 percent more than the number who supported gay marriage the following year. In 2011, however, 50 percent of Americans believed that marijuana should be legal, an increase of 22 percent. In the same year, as I mentioned above, 53 percent of Americans expressed support for gay marriage, an increase of 26 percent.

Over the almost the same period, in other words, support for legal marijuana started and ended in about the same place as support for gay marriage. Yet no one seriously suggests that we’ve conned by the pot lobby.

These observations are not a scientific analysis, but they are suggestive of a few conclusions. First, the rise in support for gay marriage is a reasonably close fit with the historical pattern for change on controversial social issues. It has increased more quickly than support for interracial marriage or legal marijuana. But not so much that it raises suspicions of coercion. Second, it takes a long time for changes to traditional norms to achieve substantial support: in 1958, for example, interracial marriage had just 4 percent support. Once support for such changes reach a threshold of about 25 percent, however, it can increase very quickly. Finally, it is very difficult in modern America to sustain any laws that appear to limit individual freedom. As Matt K. Lewis has argued, the culture war was never much of a contest.

Social conservatives don’t have to like these conclusions. But they make better sense of the apparently unstoppable wave of support for gay marriage than Caldwell’s dark suggestion that we are being marched in quicktime along the road to serfdom. Opponents of gay marriage have no choice but to obey their consciences. But that does not require a flight from political and cultural reality.