Gen. George W. Casey Jr. joins Company Commanders and 1st Sergeants during a "tactical freeze." Chief of Staff of the Army Gen. George W. Casey Jr. joins Company Commanders and 1st Sergeants during a "tactical freeze" portion of a Full Spectrum Operation exercise at Ft. Polk, La., on Oct. 23, 2010. The Full Spectrum exercise focuses on facing and defeating a hybrid threat representing both an insurgent force and an organized military force. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 551770-H-ZSV12-498.jpg Photo Gallery