By Steve Holland and Patricia Zengerle WASHINGTON (Reuters) - President Barack Obama said on Thursday the United States has **t yet developed a strategy for confronting Islamic State in Syria, an ack**wledgement that a decision had **t been made on whether to launch air strikes against the militant group. Obama's comment during a White House news conference before a meeting of national security advisers about how to proceed against Islamic State drew criticism from Republicans and a clarification from White House spokesman Josh Earnest.