Through the Lens of History: Gay Marriage

I've always been amazed by the willingness of social conservatives to say and do things they must know will be viewed harshly by future generations. Take for example, Gov. Rick Perry of Texas, who recently went out of his way to demonstrate his anti-gay bona fides to the Texas voters. Putting to one side whatever he actually believes about gay marriage and gay rights, can't even Rick Perry see the writing on the wall? Is he so blind that he cannot see how harshly his actions will be judged in just a matter of decades? He must be aware of history's inexorable march toward greater tolerance, toward greater equality; he's witnessed it in his own lifetime. He must know that in a few decades gay marriage will be a fact of life and that people like him, who went out their way to prevent it, will look just as ignorant and bigoted through the lens of history as previous generations of social conservatives. Why is it that each generation of social conservatives thinks that it will be the one to stop history's march? Why are so many conservative politicians willing to tarnish their historical legacies? I just don't get it. I guess the desire for short term political success overpowers the desire to be judged kindly by history. That's pretty sad.