Continued from page 1

Afghan thievery, not treachery, was judged the chief threat. Thus the killers had unfettered access and moved about without arousing suspicion.

Only 10 designated Afghan security personnel were supposed to be in the compound, but U.S. guards were given no access roster. Unknown numbers “freely entered and exited the compound unchecked,” an Army investigator found.

The Americans had been told to treat the Afghans as if they were mingling in Iron Horse Park, a recreation area on their home base, Fort Carson, Colo., according to a staff sergeant who was present but whose name is blacked out on his sworn statement to investigators.

The Americans had convinced themselves, 10 years into a war in which the successful outcome depended on empowering local security forces, that they could trust their Afghan colleagues.

That was a deadly miscalculation in this instance and dozens more in the months that followed as growing numbers of Afghan troops turned their guns on their coalition partners.

As the attacks mounted this year, U.S. officials in Kabul and Washington insisted that these were “isolated incidents.” They routinely withheld details and, until pressed by the AP, did not publicly disclose attacks in which coalition troops were wounded but not killed.

At least 63 coalition troops – mostly Americans – have been killed, by the AP’s count, and more than 85 wounded in at least 46 insider attacks so far this year. That is an average of nearly one attack a week.

In 2011, 21 insider attacks killed 35.

The attack that killed Capts. Lawrence and Russell in the southern city of Kandahar was the 17th of 2011.