What would I say?  Perhaps this:  "Don't we have problems enough without falling for hucksterism?"

Let's assume that the Bangladeshis and Ohio voters haven't fallen for hucksterism, but that they are instead (several years from now) responding to many credible studies that present an option that they think looks hugely better than the alternative. What would you say if they were well informed, rather than being dupes?

The disgusting huckster-quote is from the Heartland Institute's article, and is a statement made by "Patrick Michaels, professor of natural resources at Virginia Tech University and past president of the American Association of State Climatologists". Wikipedia tells us that Michaels is "noted for his views as an opponent of global warming theory", "edits the World Climate Report, published by the Western Fuels Association", and gets money from the oil industry.

This quote illustrates my point. The sunscreen fix makes a great excuse for telling people not to worry about CO2 emissions. It seems likely that it will be pushed, and we can see already that it can be hyped beyond any factual basis. What Michaels says tells us nothing about whether it is in reality a good option by rational human and ecological standards. Opposing whatever the other camp advocates is one way to put them in control of what you think and do. (Look at how Osama played Bush.)

We have absolutely no idea of the ongoing, long-term consequences of the recommended sulfer dioxide application.  We may know it would counter-act CO2 loading, but we do not know what else it would do.  We do know it moves us into "uncharted territory"--an innocuous-sounding but alarming phrase that means we have altered our situation to the point where past survival-knowledge no longer applies.

But we do have some idea of the long-term effects, and can get a much better understanding before anyone commits to anything (including reflexive support or opposition, I hope). Nature's demos have lasted a few years (some lasted longer than Pinatubo), and this is a substantial step toward long term.

For example, it is my impression that ozone effects equilibrate faster than that, and that we've therefore already seen the long-term effects.

The SO2 precipitation effects are simple to predict: what goes up later comes down. The magnitudes are known, and would barely offset a year's improvement in pollution control.

The reduction in sunlight is the main remaining source of effects, but these effects are what climate modeling is supposed to tell us about. They would be modeled and argued ad nauseam long before anyone would actually do anything. And the main, unarguable effect would be global cooling. Nature has shown us how this works.

You say that "it moves us into 'uncharted territory'". If we weren't already plunging into uncharted territory already, there'd be no reason to discuss this in the first place. Slowing or reversing global warming isn't plunging deeper -- it is restraining a plunge that is already in progress.

Words and ideas I offer here may be used freely and without attribution.