The only factor that has any bearing is whether total emissions drop to an acceptable level, and are projected to continue doing so. Under such a scenario, "try

The only factor that has any bearing is whether total emissions drop to an acceptable level, and are projected to continue doing so. Under such a scenario, "trying to" limit carbon emission would be a moot point. There is no reason to believe geoengineering in itself would lead to people throwing up their hands at the problem. The entire point is to aggressively lower emissions. Notwithstanding, this is already a solved problem for the long-run, just not the short-run. Renewables are heavily invested and improve in efficiency and cost perpetually. Battery/storage is also improving. Even previously non-abatable tech is starting to see emission-free innovation and nuclear is helping bridge the gap (or should). The issue is that demand for fossil fuels in East Asia is growing faster than innovation lowers it. I agree however that we don't have time to wait for the downcurve to play out naturally through the market. Some level of policy may still be required to both limit fossil fuel use and accelerate adoption of alternatives. This is an imminent problem that will cost billions and some lives.