Militant Imams Under Scrutiny Across Europe By DON VAN NATTA Jr. and LOWELL BERGMAN ONDON, Jan. 24 - In nightly sermons broadcast on the Internet, Sheik Omar Bakri Muhammad, a 46-year-old Syrian-born cleric, has urged young Muslim men all over the world to support the Iraq insurgency on the front line of "the global jihad," investigators say. He struck a similarly defiant tone this month at a rally attended by 500 people at a central London meeting hall, where a giant screen behind him showed images of the World Trade Center falling. "Allah akbar!" - "God is great" - some...