A Canadian counterterrorism investigation that led to the arrests of 17 people accused of plotting bombings in Ontario is linked to probes in a half-dozen countries.Well before police tactical teams began their sweeps around Toronto on Friday, at least 18 related arrests had already taken place in Canada, the United States, Britain, Bosnia, Denmark, Sweden and Bangladesh.The six-month RCMP investigation, called Project OSage, is one of several overlapping probes that include an FBI case called Operation Northern Exposure and a British probe known as Operation Mazhar.At a news conference yesterday, the RCMP announced terrorism charges had been laid against a...