“As a result, more people have the ability to harm us or deny us the ability to act than at any point in my life. And that’s the security paradox.”
I think in context of his quote, he has framed this in reverse order.
“…and they’re proliferating vertically, down to non-state actors, especially insurgents, terrorist groups and even transnational organized crime. “
means that the lethal and destructive technologies are able to harm us physically by pounding on our structure, while
“They’re proliferating horizontally across advanced militaries in the world,…“
means that the lethal and destructive technologies are getting inside our OODA loop and, culturally, preventing us from Acting.
It is a subtle difference, but I think one worth noting, as the General is noting two different forms of lethal and destructive technologies. One form can be thought of as weapon systems, while the other is represented by the different forms of social media taking shape.
The means-to-an-end is always in resources, so I think what the General is saying that lethal and destructive technologies give more people the resources towards an end.
The job of social media is to make sure it is a good end, as it is, because of lobbies, almost impossible to control weapon systems.