In Afghanistan, the killings are called "green on blue" — that's when an Afghan soldier or police officer turns his gun on a NATO ally.
There was a wave of such violence just last month after U.S. soldiers accidentally burned Korans. Over the next week, six Americans were killed, apparently at the hands of Afghans working with the U.S.
The top U.S. and NATO commanders in Afghanistan think they have some answers to this recurring problem, and it's up to U.S. soldiers like Capt. Joe Fritze to see if they work.
Every May, Russia displays its military might in a parade on Victory Day, commemorating the surrender of the Nazis to the Soviet Union in World War II.
The marching men and rolling tanks put on an impressive show, but Russia's military, and especially its defense industry, has fallen on hard times.
"The industry, much like other parts of the economy, hasn't seen proper investment for over a decade, if not more," says Lilit Gevorgyan, a Russia analyst for the defense industry consultant IHS Jane's.
The news from Afghanistan remains grim as protests and attacks continue over the recent burning of some Qurans and other Islamic materials at an airbase controlled by international forces. The violence and unrest has also, The Washington Post writes, "exposed a crippling weakness in the American strategy to wind down the war."
Uncertainties surrounding the future of the NATO mission in Afghanistan are of particular concern for an area near Kabul that French troops have controlled for the past decade. France now plans to withdraw its army a year ahead of schedule, sparking fears of a potential crisis in Kapisa province.
On a plateau amid the towering Hindu Kush mountains, Hukum Khan, a 31-year-old Afghan farmer, says the presence of French troops hasn't made much difference in his life in the past 10 years.