"The people whom you resent so badly do not disappear at the border magically; they produce as much CO2 and methane before they cross as after; maybe more because they drive older trucks with no emissions regulation."


                     Frankly, I don't think so. If they refuse to deal with reality and won't adopt any kind of family planning, when they find themselves in a standing room only situation, there won't be any place to drive trucks. This is strictly a circumstance of their own choosing.