Associated Press: Thrown on the defensive, President Barack Obama acknowledged his administration could have done better in dealing with the biggest oil spill in the nation’s history and misjudged the industry’s ability to cope with a worst-case scenario. Obama will make his second tour of the battered Gulf Coast on Friday. “I take responsibility. It is my job to make sure that everything is done to shut this down,” Obama declared in a lengthy news conference at the White House on Thursday. As he …