French Ambassador to the United States Gerard Araud, left, escorts President Barack Obama after Obama signed a condolences book during a visit to the French Embassy, on Thursday, Jan. 8, 2015, in Washington. Masked gunmen stormed the Paris offices of a weekly newspaper that caricatured the Prophet Muhammad, killing at least 12 people, including the editor, before escaping in a car. It was France’s deadliest postwar terrorist attack.