A bearded Imam kneels down to talk to a group of young Muslim boys. "Do you know what the word Jihad means?" he questions. "It means Holy War." In ghettos like this across Europe, disaffected youngsters are being targeted by terrorist networks. Nasser is just one of the recruiters. He is a jihad soldier for the Salafist Brigade, an organisation linked to Al-Qaeda. He enlisted as a young man and fought in Chechnya and Bosnia. Now he spends his time trawling the streets of Holland looking for young men to recruit to his cause. "We go to areas where lots of Muslims and Arabs live," he explains. "Those who are vulnerable are more likely to go than others." Holland is vulnerable to extremist groups because its liberal laws are easy to manipulate. As Nasser explains: "In Holland we're not hassled by the security services." He also launders money there to support his cause. Combating these groups would involve introducing many strict laws. But is Holland ready to jeopardise its liberal society by doing this?