Inside Story - Islamic State ‘beheading’: A challenge to US?

The Islamic State group sends a graphic "Message to America" said to show the beheading of an American journalist. Laura Kyle speaks to Abu Rumaysah - an Islamic activist, who recognises the Islamic State Caliphate in Syria and Iraq; Shiraz Maher – a senior research fellow at the International Centre for the Study of Radicalisation at Kings College London; and Patrick Co-burn - Middle East correspondent for the Independent newspaper, and author of the book: The Jihadis Return: ISIS and the New Sunni Uprising.