Politico: A dirty little question is arising from the Senate’s global warming bill: Just how much should companies pay for their pollution? The legislation, up for floor consideration later this spring, would use a cap-and-trade program to cut greenhouse gas emissions from manufacturers and other polluters by 70 percent by 2050. Companies would receive a certain number of pollution credits, and the rest would be auctioned off. Afterward, larger polluters could buy extra allowances from greener …