This is a very interesting subject, although to me more than a bit scary, the ultimate decisions on these projects lie with the funding. The funding will come from the USA no doubt and that leaves Money hungry Congressmen and Senators making this decision. Usually less for thought is used and immediate gratification wins over. I would be concerned with a low orbit sun shade ( or a 100 of them) affecting the weather patterns we now have. I think it is pretty clear that weather patterns in the last 10 years have changed dramatically and I'm not sure accurate history of weather goes back far enough to predict that our current status is an historical repeat. I guess I'm on the page of lets develope what we have on the planet to make an impact before we try and go to space to solve our energy problems and of course big money and again big control of a resource. I don't want to be CHICKEN LITTLE here BUT is the sky falling!