Same Facts has a nice post tying drug addiction and political demagoguery - sometimes you can only aim for health improvements instead of fully quitting the drug, and it's similarly an issue in politics:
Thus, in some cases, the right policy is to give injection drug users access to sterile needles. In others, the right policy is to give grandstanding congressmen some way to pander to ignorant voters without crashing the economy. We all wish that heroin users would stop using. We all wish that Congressmen would not demagogue the debt ceiling. Neither wish will be granted soon.
I invite reflection among those who have low opinions of politicians and simultaneously advocate for perfect solutions at the expense of solutions that are politically feasible. Those two positions work well together if you're primarily interested in expressing contempt, but not if you're trying to make progress.
With the end of the disastrously expensive space shuttle program, the perfect solution is to let the private sector carry on manned "exploration" of areas that robots explored decades ago, and switch the federal government funding to something beneficial. I see little point in talking about that solution.
Harm minimization, or successful harm mitigation, means alternatives that keep most of the federal money in the same states that it's spent in now, even in some of the same institutions in the same states. Obama's plan for partial privatization of the manned space program might be the best feasible option. I've thought about replacing it with something entirely different, an advanced technology rescue service, but that might be a bridge too far. Maybe we can gradually reduce the scale of the program (an aside - Republicans are fighting for the big-government, socialist style old program instead - how typical).
So, carbon cap and trade. Any number of people have pointed out how a simple, universal carbon tax would avoid all the problems of the compromised cap and trade programs in various parts of the world. Australia's example suggests it is possible to get a modest carbon tax through - but one with many exceptions and that transitions into a cap-and-trade scheme.
Taking a harm minimization/benefit maximization approach, rather than a rigid rationality or nothing approach, will get a better result. I'm all for a carbon tax, but won't let that stop me support capntrade as well.