The emissions that we had from the 1800s to 1950 were under 200 billion tons of CO2 based on that graph--total. That CO2 mostly stayed in the atmosphere, but if we had kept emitting at 1950 levels in perpetuity we would have been fine. From 1950 to 1970 we emitted roughly another 200 billion tons, tripling our annual output. In the 1970s we emitted almost 200 billion and then in the 1980s we emitted over 200 billion. That's not cleaning it up. It was getting worse! That's why the temperature started to take off in the 70s and 80s. Our combined output in those 2 decades matched all of human history before that point. Then we emitted even more in the 90s, 00s and 10s.

This isn't related to air pollution or acid rain or smog. We largely addressed those problems long ago by lowering the pollutants from power plants and vehicles (the original purpose of the Clean Air Act). We haven't even turned the curve over on CO2 emissions. All told, we've emitted about 1500 billion tons of CO2 and most of it has come since 1990. Using the fact that nothing had changed before the 1970s is really missing the point.

What I'm saying here is that your caveat about there being much more at play is largely false. The CO2 is the vast majority of the cause. How we cut ourselves off from CO2 is a policy question. But if you're basing your analysis of policy on the assumption that human CO2 emissions aren't the cause of the global temperature increases that we're seeing then I'm telling you, with all due respect, that you're wrong. I'm not trying to be a jerk about it, but it's just true.