Like previous student-led boycotts of tobacco companies and banks with operations in South Africa, the global fossil fuel divestment campaign is rumbling into action. With high profile backing from the Guardian newspaper and a student blockade of the university administration at Harvard this week, its supporters want to cripple the world’s oil and gas companies by striking where it hurts — at their finances.

The movement is an elaborate charade, which is too inconsistent and impractical to succeed. Even the campaigners admit they are not entirely serious — that their chances of shutting down ExxonMobil or Royal Dutch Shell are roughly zero, and that their own lights would go out if they did. It is a political campaign for carbon taxes and green laws in financial disguise.

The proponents are unworried by the inconsistencies of their demands. When I spoke to Bill McKibben, the movement’s founder, on the picket line at Harvard this week, he was happy that “the movement is blowing up in an encouraging way” despite his alma mater’s refusal to comply. Apart from a lack of sleep, having spent one night “in some bushes in a sleeping bag”, he was feeling extremely buoyant.