Understanding France's special brand of state secularism, 'laïcité'

France's particular brand of secularism, known as "laïcité", is considered a backbone of the French Republic. And yet this separation of church and state is a touchy subject and often misunderstood. Its backers say it's the glue that lets the French live together in harmony despite their differences, but critics say it's anti-religious and increasingly used to stigmatise Muslims. Francis Monte and Adel Gastel take a closer look.