WASHINGTON (Reuters) – President Barack Obama said on Sunday the U.S. economy was expanding but not at a robust enough pace and there was no "magic bullet" that will fix its problems. Obama said in an NBC interview that the batch of grim economic data over the past few weeks was something his administration had anticipated. ... "The economy is still growing, but it's not growing as fast as it needs to," Obama told NBC in the interview in New Orleans, where he stopped after a vacation on the Massachusetts island of Martha's Vineyard. Obama faces a dilemma in trying...