Memo to Miliband: resign now to win the leadership
Of course, the resignation has to be delivered graciously. John Denham's thoughtful departure from the Government over the Iraq War is a good model. Ed should say something like. "I cannot in good conscience support this measure to build another runway. I am not sure that if I do so I can be certain of being able to look my grandchildren in the eye. I support the Prime Minister, but I cannot support this plan. If we are to tackle the threat of climate catastrophe, our ideas of progress need to be re-examined. Building another runway to take another 200,000 flights amounts to a blind refusal to accept the consequences of climate change."
Labour MPs are being, in the words of one, "quadruple-line whipped" into the lobbies order to pass this bill tomorrow. Of course, the technical arguments are complex. And it may well be that in the broader scheme of things, a runway is not - in carbon terms - the biggest deal. There may be some economic downsides to a decision not to proceed. But the politics are brutally simple, and the symbolism of the decision is gigantic. This will be the most fought-over, highest-profile battle between the environmentalists and the economists.
There is a generational dimension here, too: younger politicians understand and feel the climate change issue in a way the baby boomers simply do not. It is not a coincidence that the younger leaders, Cameron and Clegg, will lead the parties into the opposing lobbies. Brown is forcing a whole generation of Labour ministers onto the wrong side of the argument over the biggest issue their generation will face. Make no mistake: those Generation-X ministers who vote for the runway will be recanting and apologising within a few years. But if one of them is brave enough to act now, they will immediately put themselves at the head of the pack for the leadership contest. Go on, Ed. Life's too short. Resign - and you might reign.