Though I agree with environmental conversation I would like to point out the distinction between that and government tax. The latter is clearly disguised as the wolf in sheep's clothing in order to extract money from people and industry.
The inevitable outcome will be the implementation of taxation and no progress on the environmental responsibilites. So from my perspective NO TAX. Aircraft for rather obvious reasons cannot simply switch to another powerplant as easily as ground based motor vehicles and also power stations that can generate power by ever increasing methods.
As someone earlier in the thread quite rightfully pointed out this aviation is nothing more than another easy target as it's an industry and won't affect the votes whereas consumers are to be exempt. Indeed industry has alot of waste but that's because it's on an industrial scale yet if you compared the waste per unit to that of an average household you'll probably be surprised to note that industry in some respects is alot more efficient.
Open eyes to the environment and push for better education about what's really going on about the environment and what we can realistically do about combatting this problem. Let's have a short and medium term plans with a longer outlook rather than political headline grabbing "Ministers to have a big get together and jolly to sort out the world's environmental problems". Other countries around the world are making progress and it's not just the self appointed 'west' that can save the world.