Geez. Don't know who you these "people on the left" you guys are encountering, but you're sorely underestimating them. I come from a family, and background, of liberals who all possess PhDs, MDs, JDs, etc., and they can all pretty clearly articulate WHY they believe what they believe. The sort of hubris displayed in this thread is giving me a pretty clear indication of why our movement has taken such serious hits of late.
If you approach our opposition in the belief that they "are comfortable with this ignorance," yes, you certainly will incite some hostility. And if you're watching "smug looks dissolve into rage" you are not effectively debating. We're not doing this for fun.