Sure. That's always the way with rights which have not been long-enshrined in popular culture -- either they aren't rights because they're only there on suffrance of the majority, or they aren't even that, because they can't be wedged into a constitution that's too hard to change. It takes time. It takes way too damn much time, because the only way to secure rights is to engrain them so solidly into the mindset of not merely the majority but the overwhelming majority that even those people who don't like them wouldn't think to try to change them; it just wouldn't occur to them as possible.

Constitutions that move quickly can do no more than state the current viewpoint on who has what rights... and as you say, that can change at any moment. Constitutions that move slowly can provide some ballast for rights once they have been included, but guarantee they won't be included until long after the people would've accepted them. It's a question of which evil one prefers.

Ultimately, the only way gay marriage rights will be protected is through the slow change of enough minds that the ones which don't change will have no leverage, and then will die out. I don't like it. But I don't see any other way to make change secure.