US intelligence analysts have authenticated the video released by the Islamic State depicting the beheading of James Foley. In the video, a masked member of the Islamic State threatens to kill more Americans if the U.S. military continues its air strike campaign in Iraq. President Obama responded this morning: "Friends and allies around the world—we share a common security and a common set of values that are rooted in the opposite of what we saw yesterday. And we will continue to confront his hateful terrorism and replace it with a sense of hope and civility. That’s what Jim Foley stood for." Dion Nissenbaum is the national security reporter for the Wall Street Journal.