US soldiers have intervened in during natural disasters such as the 2010 earthquake in Haiti. But a disease outbreak is more complicated. SSgt. Chad Chisholm/U.S. Dept. of Defense hide caption

itoggle caption SSgt. Chad Chisholm/U.S. Dept. of Defense

U.S. Maj. Gen. Harold Greene was visiting an Afghan military training academy Tuesday when he was shot dead by an Afghan soldier, who was subsequently killed. Afghan troops who knew the attacker say he disliked the Taliban and they aren't sure what his motive was. U.S. Army/Getty Images hide caption

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Vietnam veterans Melvin Morris (center), Jose Rodela (obscured) and Santiago J. Erevia (left) received the Medal of Honor from President Obama at the White House on Thursday. Win McNamee/Getty Images hide caption

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The photo that has offended many. The soldier responsible for posting it on Instagram has been suspended and an investigation has begun. Wisconsin National Guard Facebook page hide caption

itoggle caption Wisconsin National Guard Facebook page

New York Sen. Kirsten Gillibrand (center) and Missouri Sen. Claire McCaskill (right) are at odds over the best way to respond to military sexual assaults. J. Scott Applewhite/AP hide caption

itoggle caption J. Scott Applewhite/AP

U.S. soldiers look at a crane that tipped over while trying to move a CHU, or Containerized Housing Unit, at a small COP, or Combat Outpost, in southern Afghanistan. A dozen years of war in Iraq and Afghanistan have created a whole new military vocabulary. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

Defense Secretary Chuck Hagel. Chip Somodevilla/Getty Images hide caption

itoggle caption Chip Somodevilla/Getty Images

Members of the U.S. Marine Corps listen to President Obama during his visit to Camp Pendleton, Calif., in August. Kevork Djansezian/Getty Images hide caption

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