Former National Security Adviser H.R. McMaster joined ‘The Story with Martha MacCallum’ on Monday and reacted to the hundreds of Afghans running alongside the U.S. Air Force transport plane as it moved down a runway of the airport in Kabul, Afghanistan.

AFGHANS WHO CLUNG TO DEPARTING US PLANE FALL TO THEIR DEATH IN CHAOS THAT LEFT 7 DEAD: OFFICIALS

H.R. MCMASTER: It's heartbreaking, it's frustrating, you know, I think it's wholly unnecessary. That's what's so sad about it, Martha. I mean, we delivered psychological blows to the Afghan security forces into the Afghan people far beyond the physical blows that the Taliban was capable of delivering. You know, this is by our precipitous withdrawal. And I think just the utter lack of planning for what we knew, what we knew would be a humanitarian catastrophe of colossal scale.

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