By JOSH LEDERMAN Rushing to curb political fallout, the White House pushed back Wednesday against harsh criticism in a new book by former Defense Secretary Robert Gates that questions President Barack Obama's war leadership and rips into Vice President Joe Biden.The tell-all memoir from Gates has created a splash in Washington, casting a negative light on Obama's national security operations by detailing a high level of discord among the small team that made key decisions about the wars in Iraq and Afghanistan.