Former CIA Director David Petraeus detailed Saturday on "One Nation with Brian Kilmeade" why the Russian military has had an "underwhelming performance," saying it wasn't trained to the standards anticipated by the United States or other NATO countries' militaries. 

DAVID PETRAEUS: I think an awful lot of people got caught up in the narrative that President Putin had invested a great deal in his military, had brought it back from the depths of the post-Cold War period and seemed to take from these limited operations that were conducted, for example, in Syria, which was really mostly just Russian Air Force dropping bombs in an area where they had complete air supremacy, but took from that, that this is a really much improved military force. And we just haven't seen that.

They have failed to integrate their ground maneuver and their air assets, something we thought they would use to great effect. That's really the essence of blitzkrieg going all the way back to, say, 1939, and they haven't been able to achieve combined arms effects. In other words, using armor together with infantry, with engineers, with indirect fire, mortars, artillery, drones and all the rest of that, they just have not seen any of those kinds of operations, which again, we take for granted and are just the normal standard.

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