Chris, Slow Down.
I think you may be so wrapped up in trying to defend AGW that you're missing the point. Just because someone is skeptical of the AGW theory (and its attached 'solutions') does not mean they are a foaming-at-the-mouth, wild-eyed, knuckle-dragging, heretical, Neanderthal (or Conservative) - this poster exempted, of course. Uncertainty is not the same as ignorance or stupidity.
First, in your 4 points, change "global warming" to "climate change". In other words, instead of focusing on warming, let's open the door to include that fact that temperatures go up and down (historically proven). Second, add # 1-B... "Climate Change is happening, but we don't know (understand) all the causes." I think that's what Joe Miller is trying to say. I'm not convinced we need to go any further down the list (although many do, on both sides). The motivations or syllogistic thoughts behind where folks stand on the issue aren't really of consequence.
My take on Joe Miller's statement you quoted -
A. Joe's correct in saying MAN-MADE climate change has NOT been proven. (Theorized, but not proven). That's not the same as claiming Climate Change itself is not proven. It's the MAN-MADE part that is under question. I've made this exact point multiple times. We just don't know enough (yet), to state, with certainty, that MANKIND is the cause (or the solution).
B. Joe's correct saying that for this (possible) problem, various 'solutions' have been proposed. It's also correct that NONE of those solutions have been proven to 'address the issue'.
C. Joe's off-base at the end because, Yes, some cost-benefit analysis for those 'solutions' *has* been done. And the cost is high. Very high. Is it worth it? Why are even talking about it? Prove it (the problem AND the solution) first, then we'll talk.
Conclusion: We have a observations of the Real world that may or may not indicate a problem. We don't know what the cause is. We don't know we (as humans) can do anything significant about it. We have some proposed 'solutions' that have not been proven to work. Everything that's proposed is Massively Expensive.
SO - To answer your question: NO. I don't think its odd to argue against a solution for a problem that doesn't exist (or hasn't been proven to exist). People do that all the time. IMHO, It is perfectly rational to MAKE SURE we understand the problem, *before* rushing off to implement solutions, especially when we have NO PROOF the solutions will actually work.
Joe's (political) point is that his primary opponent - an incumbent Republican, as I recall - isn't looking at the entire picture before taking a position on an expensive and potentially USELESS 'solution'. The election results speak for themselves - Politicos and bureaucrats of all stripes should take careful note - Folks don't like what they're doing about the Real Problems, let alone what they propose as 'solutions' for 'problems' that may not exist. This is an indication such feelings are not about party anymore - and that's a Good Thing.
I find Joe's attitude and approach on this issue refreshing. (Caveat: I don't know enough about him to comment on other positions he may hold.) And, I believe we will do BETTER in the long run with a Congress composed of calm, rational-thinking people taking the appropriate steps before choosing a course of action than we have with the agenda-driven, self-important, we-know-whats-best-for-you-just-trust-me... bunch of clowns we've had for far too long.