There is just a fundamental difference in the mindset between the average liberal and conservative now. It's not just a series of minor policy differences but rather a huge, uncrossable ideological chasm. Just a total different way of viewing the world at this point. Liberals inherently think the world is unfair/dangerous and government exists to protect and provide for us because otherwise we can't survive on our own. Conservatives inherently think the world is understandable and rational and man can seize his piece of it with hard work.