The thing that troubles me most about current politics is that it seems to be fought out exclusively along an axis between socialism (high governmental control) at one end and libertarianism (low governmental control) at the other end. What bothers me is that while there are Christians all along this spectrum, it is anchored at either end by aggressive atheists - Marx at the socialist end and Ayn Rand at the libertarian end.
Because of this, in minds operating along this continuum, God may seem to be irrelevant. What I mean is that for an argument to have some chance of being accepted in this arena, it needs to be framed in terms that fit this socialist-to-libertarian spectrum.
For example, I could argue that God wants marriage to be just between a man and a woman, but if I did so I'm afraid I would simply be ignored or laughed at because the "God" concept seems out-of-bounds to those who are stuck along this atheistic continuum.
Instead, if I wish to defend marriage as being solely between a man and a woman, I would argue (and have) that an institution can own the rights to a word ("Coke," for example, belongs to the Coca Cola Company so Pepsi and others can't label their products "Coke"), so, in the same way, a long-time institution such as marriage should have the right to retain the word "marriage" to describe only the contractual relationship between a man and woman. That doesn't limit others' lifestyles, but legally others need to name their arrangement something else - a "union," or whatever.
So, if I argue within the continuum, perhaps I win over a few minds, and I'm glad if I do, but I have lost the much bigger battle. I have left God out, and that bothers me.
Perhaps political discussion needs to begin at a deeper level. Atheist socialists and atheist libertarians may be making assumptions they have not examined, one assumption being that the welfare of people is a high priority. Is it? Why? Atheism gives no reason for valuing anything, including human life. But God declares that human life is valuable. I think Christians need to take every opportunity to re-introduce God, to point out that there is no atheistic command, "Thou shalt not kill" and there is no atheistic command to "love thy neighbor." Those commands are from God, and if socialists or libertarians wish their arguments to be on firm ground when they appeal to human welfare, they need to recognize that.