* eating less beef
* not flying
* using a bicycle/train. not possible everywhere for americans, anyway, but possible for most europeans. minimum is car sharing and using a light car.
* less house heating, more insulation
If they disagree, don't worry, but make sure they know. It's expected some people are going to use violence to reduce CO2 emissions, especially for the ones that can be avoided easily.
Anyways, western rich countries will not be the ones who are hit the hardest.