sentences:  He joined the National Security Council staff in March 2005 as Director for Strategy and Defense Issues, Directorate of Combating Terrorism.His responsibilities included developing and coordinating inter-agency policy on countering weapons of mass destruction terrorism, threats to international aviation security, and maritime security policy.From January 2004 to March 2005, Tidd commanded Persian Gulf maritime War on Terror operations as Commander, Middle East Force and Commander Task Force 55.