Arguing with conservatives only makes them more sure of themselves

Scientific studies show it.

I'd like to repeat what the author of this piece (Dan Sweeny) says. If arguing with conservatives only makes them more rigid in their beliefs then don't bother, except when there are undecided people around. Then the argument can be useful if your arguments are designed to persuade the undecided that the other side is nuts.

Republicans understand this better than Democrats. Republicans, for the most part, aren't interested in converting Democrats. They are all about persuading the audience in the debate. Democrats need to understand this and adjust accordingly. They need to "get over themselves" with their persistent belief that if they could just talk sense into the opposition they can win them over to their side.

That means arguing your position in a way that persuades the audience that you are right and the other side is nuts. Fortunately, reality has a way of lending a helping hand in this endeavor.