Vegas Massacre Could Change Active Shooter Tactics

A trained sharpshooter firing from atop the University of Texas Tower in 1966 introduced many Americans to mass casualty attacks, but almost all of the large-scale shootings since then — including Sandy Hook and Orlando — have taken place at ground level with the gunman killing from relatively close range.One result: Even as mass shootings became more frequent and police departments expanded training on how to confront a gunman, officers were typically coached on close-quarters assau