I missed this, but on Thursday the Trib published a column by Jim Powell, a senior fellow at the Cato Institute (limited government, free markets, etc). 

Powell explains how federal regulation of marriage proved to be a bad conservative idea back in the days of Theodore Roosevelt. 

Polygamous families were producing more children than monogamous families and TR feared that polygamy would sweep the nation. He recommended a constitutional amendment banning polygamy. He came close to suggesting that there ought to be a law making it mandatory for monogamous families to have children.

Aside from the characters on HBO, do you know any polygamous families?  

Powell continues:

One big problem with the idea of federalizing everything is the assumption that the "right" people will always be in control.

<snip>

Mindful of historical reality, one has to consider the possibility that if the marriage amendment is ratified, it will strengthen precedents for the federal government to find new ways of interfering in people's personal lives. At least some of the interference will likely be abhorrent to the religious right.

All very excellent points.  But Powell fails to carry his argument to its logical conclusion -- its not so much federal control of marriage that's abhorrent as government control period.  Why should the Commonwealth of Pennsylvania exert that latitude of control over marital and, by default, nonmarital relationships? 

We've already seen examples of the damage that the amendments can do vis a vis blasting domestic violence convictions out of the water for unmarried couples.  People of faith should rethink this because its not just the great unwashed sinners who run into this wall of control.  If your engaged virginic daughter is beaten by her fiancee, she may have no legal recourse.  If he waits until they are married to beat her, she's all set.  That makes no fucking sense.

Powell wraps up with a call to the conservative faithful to live up to their own ideals rather than imposing them on others:

If they really want to promote traditional marriage, conservative people of faith should do two things:

First, they could marry someone of the opposite sex and set an example of how beautiful such unions can be.

Second, rather than working to close off the rights of gays, they should use their political efforts to abolish the obnoxious marriage tax penalty. Then all people of every sect and philosophy would owe them a debt of gratitude.

I'd go a bit further.  If the conservatives want to preserve the institution of marriage and protect families, they should put down their fetus signs and sign up as a foster family.  It is the best way to help put a family back together.