There is slight overall warming, but it's the uneven warming that has led to some dieoffs. The rest of the dieoffs are due to other factors as they always have been. Even uneven warming has always been around and always will be irregardless of overall temperature.
But it's warming much more rapidly during the past 50-100 years, since industrialization occurred, and a natural trend doesn't explain this.
The warming in the first half of last century was followed by cooling until the 70's, then more warming. The warming is indeed part of the exit from the last ice age and the link from human-caused CO2 to warming is only a theory.
But with some economic incentives, we could have a homegrown energy economy, could worry less about the middle east, and would be building ourselves some breathing room on climate change at the same time. What is the downside to that?
It's a decent question and I'm not opposed to incentives. But I see hybrid cars that take more energy to build and maintain. They use more energy than a car with the same gas engine in many cases like open highway travel. I see ethanol that takes more energy to produce than it yields. There are other better alternatives, I don't see any downside to subsidizing solar in Arizona for example.
I largely agree with your last post except for delegating human-caused CO2 to a mere theory. There are theories that are just recent ideas, and then there are theories that are strongly supported by evidence and research.
It's a well known fact that CO2 traps heat in the atmosphere, without it we would not have a hospitable place to live. It's also a well-known fact that we are pumping large quantities of ancient carbon out of the earth and releasing it where it forms into CO2.
So, given this we would expect "human-caused" warming to occur unless there is some mitigating factor to prevent this. But we have not found one, and instead we are seeing an accelerating warming trend, and that's why there's such a strong argument for doing something.