Trafalgar Square, central London. More than 3,000 people are in attendance at the “Rally for Islam.” A notorious firebrand near Nelson’s Column calls for jihad against Britain. Thunderous cheers roll through the crowd and echo ominously toward Whitehall. Placards demand the assassination of the British prime minster and other Western heads of state. The speaker avows that he will not rest until the black flag of Islam flies over Downing Street. He further declares that British citizens are legitimate targets in the imminent holy war because Britain assisted in the destruction of the Caliphate in 1924.