Indeed, one important aspect of this kind of research is that it must be in the public domain; i.e. no private patents.

We need all-of-the-above. Yes, we need to cut CO2 -- to net zero. And that (likely) requires large-scale systemic change. The big step there is pricing carbon. Not the only step. http://www.nature.com/news/energy-policy-push-renewables-to-spur-carbon-pricing-1.18260

But it's also clear that solar geoengineering tackles aspects of the problem that cutting CO2 does not.

We need all-of-the-above. Yes, we need to cut CO2 -- to net zero. And that (likely) requires large-scale systemic change. The big step there is pricing carbon. Not the only step. http://www.nature.com/news/energy-policy-push-renewables-to-spur-carbon-pricing-1.18260

But it's also clear that solar geoengineering tackles aspects of the problem that cutting CO2 does not.

A definite yes to education and condoms -- i.e. reproductive choice -- but that doesn't mean we don't need more (clean) energy. See e.g. www.climateshock.org and also e.g. https://www.gatesnotes.com/Energy/Powering-the-Fight-Against-Poverty

Indeed. Everything depends on the counterfactual. If we could "stop the first experiment," sign me up. Sadly, it seems neither possible nor overall desirable.