Guardian: Even in this era of costly crisis and even more expensive rescue, $50 billion is still a lot of money. That sum — perhaps even more — is what Congressional leaders and aides to President-elect Barack Obama say he will propose to build new transit lines, weatherise buildings, manufacture clean next-generation vehicles, and create new “green collar” jobs. Even more crucial than the scale of the spending on clean energy is what the President-elect says it represents to his overall …