They can be reasoned with because we talk past each other, not realizing that the other has opposite base assumptions on which they are building their argument.
Those base assumptions have to be addressed. Often times the liberal has no idea that they even HAVE base assumptions, after all, they are ASSUMPTIONS and don’t need to be examined, they just ARE.
As we grow older we become less certain, but we have become more set in our ways and have worked ourselves into situations where it is very difficult to change our beliefs.
I think it is true for most people, liberal or conservative, that most can't allow for their views to change much so arguments only serve to reinforce biases.
I think the best one can do is get someone with differing views to see that maybe you're not completely crazy for believing differently.
If the USA starts to become more conservative it will only be because a huge swath of young people today are finding it hard to get a job. If those young people want more out of life they will want politicians that create a business friendly environment so they can be successful. If those young people are OK with living off the dole then stick a fork in us. We're done.
Liberals' assumptions are nothing if not base.