They have bundled "pollution" and "climate change." Therefore, Global Warming is clearly caused by Pollution, Pollution is caused by man, so Global Warming is caused by man.
OK, pollution is bad. Climate Change (as Global Warmers rather diplomatically have re-named it during the present cooling period) is neither bad nor good. It just is. We deal with it. Global Warming or Cooling isn't caused by man, and neither is all "pollution." The crap coming out of a volcano is far worse than the bondo dust coming out of Rudy's Body Shop, and there sure is one hell of a lot more of it.
Furthermore, we can clean up Rudy's, or a coal-fired electrical plant. The entire Carbon Dioxide as a man-caused greenhouse gas hypothesis is theoretically possible.
But isn't it more reasonable to look at sunspot activity, not to mention our place in the Milankovitch Cycles, first? The Earth SHOULD be warmer right now ... but actually really isn't. "Why isn't there Global Warming?" That's the real question.
Mention "Milankovitch," "Precession," or "Axial Tilt," to the average man in the street today, and you will get the same blank stare you would get from a news bimbo on TV news.
It’s not that “pollution=global warming”, it’s that some gases will absorb/re-emit radiation at certain frequencies. Now all of those gases occur naturally, but we also produce them (primarily through combustion, but also through ‘natural’ ways like cows burping and things). It’s just a question of scale here (are we doing this on a large enough scale to have an effect?).
It’s perfectly reasonable to look at things like sun-cycles, the earth wobbling, measuring incoming radiation vs. reflected/outgoing radiation, natural sources/sinks for greenhouse gases (volcanoes and impacts have had big effects in the past, for instance), etc, and a lot of scientists do. If you legitimately study this stuff, all you do is sit around and think of factors that could affect things, and then try to model/measure them. On the other hand, you have a lot of moron hippies that just want an excuse to think industrialization is the devil, and don’t actually understand any of the science behind what they’re parroting. I put people that say “OMG, the earth had different climate in the past, global warming due to human-produced greenhouse gases is a lie!!!” into the same category. They don’t understand the science behind their position, they’re just parroting whatever someone told them and using it as an excuse to think hippies are stupid.
It’s no better when our side does it than when their side does. I would agree with your ‘blank stare’ comment, and I think it’s a shame that more people don’t study (or at least pay attention when they have it in high school!) chemistry, physics or engineering.