What is missing in the Left today is a sense of solidarity. What has replaced it is a cult of (paradoxically) individualism and uniformity. We worship great social machines but try to leave some room for individualism. You are a unique ear of grain, awaiting the equalizing force of the combine. In this respect what comes to mind is the shrine of Roma outside the Temple of Caesar.
This has major implications. Try to discuss whether other cultures have a right to decide the direction of their own cultures on things like abortion rights, gay rights, or the like and the people least affected want the most power to force others to change their ways of life.