Greg served in the United States Army for more than 26 years and became the Garrison Commander of Fort Belvoir. He has served in every major conflict in the past two decades, including Operations Desert Shield/Storm in Kuwait; Operation Joint Forge in Bosnia, Operation Enduring Freedom in Afghanistan and Operation Iraqi Freedom. His greatest challenge came in Iraq, where an IED attack cost him both legs above the knees. Despite this, he remained on active duty and continued to inspire many with his message of courage and perseverance. In 2007, Tom Coughlin, New York Giants head coach, asked Greg to meet with the then-struggling team. He talked to the players about teamwork, perseverance and adversity. The Giants have heralded the key inspirational role he played in their unprecedented season culminating as victors of the 2008 Super Bowl. Greg also established himself as an actor, acting in several movies and TV shows. In 2012, he starred in “Battleship” portraying the role of Lieutenant Colonel Mick Canales.