In reading an article at National Review Online today, I came across a 'meditation' by Yuval Levin on conservatives vs liberals.
To my mind, conservatism is gratitude. Conservatives tend to begin from gratitude for what is good and what works in our society and then strive to build on it, while liberals tend to begin from outrage at what is bad and broken and seek to uproot it.
I believe that this stems primarily from whether one has a Biblical worldview or not. With a Biblical worldview, we are grateful for the good that we have and seek to preserve it because we know that the very nature of man is such that we generally screw up when we seek to 'improve' things - either destroying the good or creating new problems we never dreamed of. Those of us who are older can testify that we have managed to screw up a lot that was good during our lifetimes.