This is CBS Eye on the World.

Here's John Batchelor.

The tragedy in the District of Columbia these last days has right now an alleged shooter named

Ramanula Lackinwal.

He's 29 years old, we're told an early assessment of his background.

An Afghan National, he's said to be residents in Bellingham, Washington. Most importantly,

he's identified as a veteran of the Afghan National Army, special units, special forces.

And when I read over the story, I immediately think of Long War Journal all these years

of the Afghan nationals turning into an army that appeared credible in the last year, 21, but was not.

The Afghan National Army that bugged out every time

it was challenged by the Taliban in their march to Kabul. And I welcome Bill Rachio, the senior

fellow of the FD, who keeps the Long War Journal, because Bill taught me over the years to pay special

attention to what was called blue on green.

And Bill is remembered that he testified to Congress about blue on green.

And in the most general sense, the tragedy in D.C. with the death of the Young National Guards

and the shock to the nation at the ambush. And the most general sense, it looks to be

blue on green, long delayed, but here it is. Bill, a very good evening to you. Welcome. What was,

what is blue on green? What does it talk to? Thank you. Hello, John.

Good evening.

Yes, so blue and green attacks, this is something that were quite prevalent in Afghanistan,

particularly during leading up to the U.S. surge in Afghanistan from 2009 to 2013.

These are attacks where Afghan security personnel, be it the National Army or police or other security personnel would attack American and NATO forces.

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