Well if one side is right, then we've blown some money that we probably would've blown on a bunch of stupid shit anyway. We'll become more sufficient and develop new eco-friendlier technologies that we probably should be anway.
If the other side is right .... then we could be fucked as a civilization.
I'd probably err on the side of caution seeing as how we don't exactly have an "extra" Earth laying around just yet.
Once we can terraform/colonize other planets, hey go nuts and take a shit all over Earth if you want, free fracking and extra CO2 for everyone.