Look at the historical data.
It should jump out at you that the past 10k years of relative climate stability is an anomaly, and that rapid (on geological scales) swings in temperature and CO2 are the norm. That whole system is not well understood, though I believe solar variation is the leading hypothesis right now. On a scale beyond a century, there's just no reason to expect climate stability in the first place.
On a decade by decade scale, there's no evidence of warming in the 17 years of reliable satellite temperature data. The null hypothesis - that average temperatures aren't changing - has actually been the best predictor of climate data since the late 90s, odd as that may sound.
The simple fact is: the atmosphere and oceans are chaotic systems, with a variety of positive and negative feedback loops, quite difficult to model, and you can't talk about climate change in a scientific way without doing so. There are no obvious conclusions to draw, as the system we live in is simply too complex for hand-wavy, back-of-the-envelope calculations to be interesting. We may simply lack the technology today to do this science properly. That's not a reason to stop - we built the LHC, proof we can do some fucking impressive technological advancement to achieve a scientific goal. But it is a reason to avoid arrogance.
Climate science is at the phlogiston / aether / Freud stage right now. That's fine, every science must start that way, and the scientific method works given time. But for goodness sake the lay believers are very much like a religion right now, complete with a list of sins and a Hell to roast in, and that's taking it too far!