How the New York Police Dept. Fights Terrorism Re "With Muslims, Using a Brush Far Too Broad," by Michael Powell (Gotham column, Jan. 31), does a disservice to New Yorkers in the way it represents both the Police Department's 2007 report "Radicalization in the West: The Homegrown Threat" and its counterterrorism strategy. As a co-author of that report, I can say authoritatively that it focuses on behavioral changes that are indicators of a turn to violence - the very signs of suspicious behavior that Mr. Powell applauds being on the lookout for. Moreover, Mr. Powell wrongly represents the report and its findings as a foil to the British and Department of Homeland Security's views on these issues. I can confirm that as of last month, when I was in London, the New York Police Department and British perspectives remain in direct alignment. The Police Department's counterterrorism strategy is based on detection and disruption - arresting individuals as they form conspiracies and turn to violence, not "trying to peer into a psyche." MITCHELL D. SILBER Director of Intelligence Analysis New York Police Department New York, Feb. 6, 2012