Japanese photojournalist Nahoko Takato, left, reacts as Japanese aid worker Noriaki Imai toasts their freedom, in this image made from television in Baghdad on April 15, 2004, after kidnappers released them. (Al Jazeera via APTN/Associated Press) It's unclear how Japan will respond to a video purporting to be from the Islamic State that includes a threat to behead two Japanese citizens. A $200 mil