Defining the sanctity of marriage

One of the new contributors at Expat Teachers's blog, MoLak-Jedi asked an interesting question yesterday:

"What I want to know is that if the sanctity of marriage is such a vital issue to the religious right - to the point that they want a Constitutional Amendment banning same-sex marriages - why don't they push for an Amendment banning divorce and push for laws against fornication?"

Let me first preface by saying that I am uncertain as to what I think about a Constitutional amendment banning same-sex marriages.

To directly answer the question, I think that is a great idea. I do believe that no-fault divorce should be made illegal. And I know very few conservative Christians who would think otherwise. No-fault divorce is pernicious and a pox upon our society. It is damaging to all involved.

So my question to MoLak-Jedi would be: "So if conservatives show vocal support for the banning of no-fault divorce, would a Constitutional Amendment against same-sex marriage be ok?"