Did you know that WWI, WWII, Korea, and Viet Nam all began under Democratic administrations? Can you imagine any of those wars being fought by today's Democrates with their pacifist, isolationist ideology? Democrates don't know how to defend the country anymore. Before Viet Nam both parties were not so extreme and were more centrist.
I think we are still experiencing shock waves from the Viet Nam war. In the late 1960's the anti-war people took control of the democratic party and the pro-war people went right to the republican party.
As for social policy, the left buys the people's votes with expensive domestic programs. Obama and the liberal congress have really gone over the line with spending and it's time to limit entitlements before we go bankrupt.
Maybe when every hippy Viet Nam war protester is dead we can get back to normal political discourse.