Global warming is frequently cited as a global problem requiring some type of global government as a solution. I attack the moral reasoning behind this kind of claim by providing a number of conditions, all of which must hold for government action to reduce global warming to be justified. I then demonstrate that, even with generous assumptions, a number of these conditions remain at best uncertain and most likely unmet.
1: Global warming is or appears to be likely to happen in the future.
2: The global warming set to happen will have negative consequences significantly outweighing any positive consequnces.
3: The proposed action will actually reduce global warming.
4: The costs of the proposed action are less than the net cost of the global warming they would prevent.
5: There are no feasible alternative solutions which are preferable in moral and economic terms.
6: We should not expect to develop any new and economically/morally preferable solutions within the next few years.
For the sake of argument, we shall take condition #1 to be true. Personally I am somewhat sceptical of this, but it is controversial and I can demonstrate that government action is unjustified even if I accept it as a premise.
Condition #2 is highly debatable. Svante Arrhenius, the first person to propose that industrialisation would lead to higher CO2 emissions, which would in turn cause global warming, saw it as a good thing. There are vast amounts of land which are useless for farming, which would (if the world warmed up) become more useful. Existing farming areas would benefit from longer growing seasons. There would be fewer deaths from diseases which prosper in cold times. Moreover, there are problems which have nothing whatsoever to do with the science of it; for example, discount rates. The IPCC has estimated net global losses at 1-5% of global GDP with 4 degrees Celsius of global warming. Given that this is over a period of 50-100 years, during which time we might reasonably expect global GDP to increase between fourfold and tenfold (compound growth at a global mean of 3.5% implies a doubling of GDP roughly every twenty years), is the loss of 5% growth really worrying enough to justify coercive action?
Condition #3 obviously depends upon the specific legislation. When I first planned this post, I assumed that it would basically be true for all proposed measures, and not having enough relevant knowledge myself I will accept it for the sake of argument. However, I will point readers to this, which suggests that programs to reduce CO2 emissions are unlikely to greatly affect global warming much - the claim is that, even if all industrialised nations reduced their emissions by 100%, this would avert at most 0.352 degrees C of global warming by 2100 AD.
One of the last acts of the previous government of the UK was to pass a bill
There are a number of reasons to believe that condition #5 is likely to be false. There may well be an Environmental Kuznets Curve; fracking allows us to meet energy needs without contributing to global warming; geoengineering could provide a (relatively) cheap and easy solution...
Finally, condition #6. Perhaps this merits a brief defence. Global warming is a long-run problem - most of its effects are unlikely to hit for decades. Given that, if there is a substantial chance that, within a reasonably short time period - say, the next ten to fifteen years - we will develop a far more efficient way of reducing global warming, it makes sense to leave off for now and enjoy the blessings of greater industrialisation, and then focus our efforts on using those technologies when they become available.
First, note that solar panels are becoming ever cheaper, and within a few years will be profitable even without subsidies (HT Noahpinion). Second, far be it from me to attempt predicting the future, but given how much is currently being spent upon measures to combat climate change one would expect some kind of innovation to be coming out of it. That is, assuming this is a genuine attempt to avert a genuine problem and not simply a massive scheme of political patronage.
To conclude, even if global warming is happening, due to the massive timescale and corresponding uncertainty, it is sensible to conclude that coercive action to prevent or reduce it is not justified.