Sure, we can divide people up into groups in any random way. But there's nothing fair about requiring people or groups to equalize their emissions, in general.

Sure, we can divide people up into groups in any random way. But there's nothing fair about requiring people or groups to equalize their emissions, in general. If you drive a semi tractor trailer, and I drive a car, then we both may need to reduce our CO2 emissions, but equalizing them makes no sense if you in fact need to transport a lot more stuff than me. The whole reason you drive a truck that gets lousy mileage is because it's more efficient per pound of goods transported than if they were loaded into passenger cars. If we want to reduce global CO2 emissions, then the only rational and reasonable way to do it is to treat every kg of CO2 equally, and not get sidetracked into other notions of fairness. I'm aware that carbon taxes, cap and trade, etc. may have a lot of problems, it's just that the practical problems of doing the right thing don't change what the right thing is. Like the saying about looking for your keys under the streetlight when they aren't there.