According to this essay in conservative journal, The National Revew,

“If everyone were in control of his appetites, there would be no need for the government to be involved in endorsing some sexual relationships while withholding endorsement from others.”

in other words,

The conservative case against redefining marriage is based on the observation of human vulnerability to temptation. Haggard confirms what we’ve said all along. It is pervasive moral weakness that makes such things necessary.

Go down, Howard Dean, go down!