Ten years ago this week, Hurricane Katrina swept through the Gulf states, killing over 1,200 people, leaving thousands more homeless, and causing over $100 billion in damage — one of the worst natural disasters to befall the United States. Nearly 70,000 troops — active duty, Reserve, and National Guard — would eventually become involved in relief efforts, the largest effort in U.S. history, according to a study commissioned by the U.S. Army Combat Studies Institute.