By the time an elaborate, time consuming, and expensive program to pollute the upper atmosphere with SO2 is seriously considered, it will be too late to find the resources to devote to such a long term project. Besides, with global warming comes increased energy consumption, so I doubt any government(s) will be too excited to commit to such a reoccuring cost so mankind can continue to increase their fossil fuel consumption.

The consumptive model doesn't always apply. Frankly, I think it is hilarious that an idea forwarded as the worst case mitigation strategy would be taken so seriously. Isn't it obvious that a SO2 program is an impractical way to enable mankind to maintain business-as-usual?