Yesterday, by the narrowest of margins, Canada’s parliament rejected a motion to affirm marriage as the union of a man and a woman. Here is a revealing report on the vote. Although this was technically a defeat for those who oppose gay marriage, in fact it shows that the battle is still very much alive. Indications are that some members of parliament will switch sides when the government offers a motion–as it is committed to do–to impose gay marriage on the country as a whole. Canada’s ruling liberal party is badly split over this issue, and Canadians as a whole are evenly divided. But those opposed to gay marriage have been much more energetic than those who favor it, and that is what is pulling the liberal party apart. The government had considered speeding up the introduction of its proposal to nationalize gay marriage–so as to get the battle out of the way before the next elections. But yesterday’s vote means that the government’s motion would probably fail. So the liberals are likely to delay a vote on national gay marriage until after the next elections. That means gay marriage will be a central issue–maybe the central issue–in Canada’s next national elections. As I’ve said before, the lesson in all this for the United States is that gay marriage is not inevitable. The huge wave of public opposition, even in relatively liberal Canada, where the public once slightly favored gay marriage but is now evenly divided, means that in the United States, where the public is clearly opposed, we can expect a far stronger response to any state-level decision to legalize gay marriage. Given what’s already happened in Canada, action by Massachusetts would spark a tremendous wave of support for the Federal Marriage Amendment. Yet Canada also shows that a patchwork of states allowing gay marriage is unstable. Fear of a patchwork is what has spurred the leadership of the liberal government to try to impose gay marriage on the country as a whole–even though these same leaders had once opposed gay marriage. So a decision to legalize gay marriage by Massachusetts would let loose two extremely powerful opposing forces–one side trying to use the Massachusetts decision to impose gay marriage on the United States as a whole, and the other trying to pass the Federal Marriage Amendment.