I truly hope that Lockheed's reactor (or any one of the other unconventional nuclear projects) comes off. However, I think we have to remember that:

- The project may not succeed; a lot of smart people have been given significant funding to try and develop fusion systems for many years. It may be that Lockheed's team have cracked it, but we can't bet on that with certainty now. Let us say that the likelihood of success is 80%; this leaves a 20% likelihood of failure.

- If the best-effort predictions of our climate scientists about what will happen if we do little or nothing to cut emissions come to pass, the consequences will be tragic and disastrous; the cost associated will be beyond a sane reckoning

- In a cost-benefit analysis, we need to multiply out the contingencies; we have a breakdown that looks like this:

Outcome A: do nothing, achieve fusion Outcome B: do nothing, fusion turns out to be harder than we thought Outcome C: regulate, achieve fusion Outcome D: do nothing, achieve fusion

In each case, we need probability * consequence. I have not got figures for a monetisation of the consequence of adverse climate change, nor for the consequence of adverse effects of regulation. However, it is plausible to me that the cost of adverse climate change may well be tens or hundreds of times the cost of some extra bureaucracy and regulation. I would also submit that the costs of inaction should be weighed more heavily than the costs of action, because effects on the climate look to be irreversible beyond certain levels, whereas effects on economic growth or the political structures we operate under may be more reversible.

As a further factor, consider the economics around energy use; to entirely prevent the use of coal, oil, gas and so on, the Lockheed system will need to profitably sell energy at lower than the cost at which all these things become entirely unprofitable to operate, accounting for the existing extraction and distribution infrastructure being in place. There is a lot of heavy industry and transport infrastructure that will not suddenly become electrified when fusion works.

Now, it may be that if fusion arrives the build-out curves and so on indicate that fossil fuels become entirely obsolete before we emit more than the maximum safe level. However, if it does not pan out like this, we may still have to voluntarily (collectively) avoid using fuels that are economically attractive even though fusion is solved.

Finally, concerns about the grabbing of power; I have more fear about the laws of physics taking power from me and my elected assembly than the laws of other men. If we push the climate in a direction that means there is not enough food to go around some years, the fact that I have a nominal freedom to burn stuff I took out of the ground will not offset the practical loss of freedom that arises from not having enough food.

Now, I do work for a charity with a goal of decarbonising the energy system in my country, and so it may be that I have been memetically co-opted and am unable to think about this properly. I really hope that is true, as I would much rather be wrong about this than right. Perhaps a technical solution will emerge; CCS will prove straightforward, new nuclear will bear fruit, we'll be able to use fischer-tropf to make fuel, nuclear desalination to make water, fleets of autonomous electric vehicles will fully optimise our transport system, and all of these things will happen of their own accord so rapidly as to render fossil fuels irrelevant before we have emitted too much CO2, and maybe this will all take place in a political climate of increasing freedom and prosperity.

God willing, I will look back on this time in my life as an old man and laugh at my foolish notions! However, on the evidence that we see today I cannot in good conscience weigh that as the likely outcome and act accordingly.