[MSN] DEN HAGUE -- She was a redheaded rebel, the singer in the family, a trash-talking, tattooed 21-year-old wrapped up in a hip-hop dream of becoming Holland's Eminem. Then Betsy found Allah.After her sudden conversion to Islam last summer, Betsy -- a name given by her family to protect her identity -- began dressing in full Muslim robes. By January, the once-agnostic Dutch woman, raised in a home where the only sign of religion was a dusty Bible on a shelf, began defending homegrown terrorists. A feud with her father over her apparent radicalization prompted her to leave home -- turning up days later, her parents and Dutch authorities now say, in Syria, where she would become the bride of an Islamic State fighter.
I blame the dusty Bible.
She also became part of a growing crisis in Europe, where a surging number of young people from non-Muslim homes are flocking to the Middle East to heed the call of violent jihad. It is happening, terror experts say, as converts emerge as some of the most dangerous and fanatical adherents to radical Islam -- a fact driven home this week by Elton Simpson, a 30-year-old American convert who joined one other man in opening fire on a Garland, Tex., contest for cartoons of the prophet Muhammad.
"I don't blame Islam," said Betsy's mother, who spoke on the condition of anonymity to protect her daughter. "I blame the people who made her believe in a radical way of life."
As the Islamic State's recruiting efforts have grown, concern in the West has largely centered on Europe's entrenched Muslim communities -- communities that have spawned more than 4,000 mostly young and socially isolated Muslims who have left to join Islamist militants fighting in Syria and Iraq. Once there, the new arrivals can transform into what intelligence officials call the most dangerous kind of radical: one with a Western passport.
Yet the Islamic State's allure is hardly confined to traditional Muslim homes. In fact, as many as 1 in 6 or 7 Europeans joining the self-styled caliphate are converts to Islam from non-Muslim faiths including Christianity, as well as nonreligious backgrounds. In some countries, such as France, the ratio of converts among those leaving is significantly higher: about 1 in 4, according to European intelligence officials and terrorism experts.
The swell of converts happens as the Islamic State appears to be actively wooing them, using savvy social media outreach and recruitment drives. A number of female converts who have joined the Islamic State, for instance, have turned to Twitter, Facebook and Instagram to encourage others to join. Increasingly, converts are being deployed in Islamic State propaganda aimed at the West, including videos for recruitment as well as for stirring fear.