One policy which I think we can realistically adopt and get countries to accept is to pursue accelerated research and development into all forms of carbon-free energy because those involve exciting new technology and give a boost to the nation that develops them first.  And the faster the development proceeds, the sooner will the cost come down.  So, for instance, India — which clearly needs to have new sources of power to replace stoves burning wood and dung, which is hugely damaging environmentally — they’ll be able to afford clean energy and not build coal-fired power stations.  So we’ve got to accelerate the R&D so that clean energy is as cheap as coal-fired power stations.  And then, without any further incentive, India and other countries will go directly to clean energy, leapfrogging the phase when they have huge fossil-fuel power stations.  So developing clean energy as quickly as possible is a sort of win-win situation for the world.  So that should be our priority.  And the amount of R&D in those areas is very small compared to defense R&D, for instance, and medical R&D. And why shouldn’t it be comparable?  Indeed, I would say that one of the most inspirational goals for young engineers should be to provide clean and affordable energy for the developing, as well as the developed, world.  That would be a very exciting development.