Once in groups ranging from US white supremacists to Irish nationalists to European Islamists, these ex-extremists have formed a network to support each other as they try to help people avoid the errors they made.
By choosing the travel to CAR, Pope Francis spotlighted the need for reconciliation between Christians and Muslims.
Prime Minister David Cameron is laying out his plan in Birmingham, home to one of the UK's largest Muslim populations, focusing on the path many youths travel toward radicalism.
The law requires imams to preach in German, closes mosques of fewer than 300 people, and bars foreign funding of Muslim organizations. The government says it will give Islam an 'Austrian character,' but many say it is anti-Islam.