California Democrat Nancy Pelosi may be trying to save the planet — but the rank and file in her party increasingly are just trying to save their political hides when it comes to gas prices as Republicans apply more and more rhetorical muscle. But what looks like intraparty tension on the surface is part of an intentional strategy in which Pelosi takes the heat on energy policy, while behind the scenes she’s encouraging vulnerable Democrats to express their independence if it helps them politically, according to Democratic aides on and off Capitol Hill. Pelosi’s gambit rests on one big assumption:...