Drones flying into NATO territory have forced the alliance to decide how to respond — if at all — to incidents inside its borders

Jeff Edmonds, a senior analyst at the Center for a New American Security and former director for Russia on the National Security Council, said the risk to NATO territory will only increase as Russian forces move further west -- and closer to the delivery of weapons that NATO is providing to Ukrainian forces.

"If and when they make progress toward the west, the more they'll probably feel they have the freedom of maneuvering to engage things coming across the border," Edmonds said of Russian forces. "One scenario here is that Russia strikes -- not really caring what side of the border -- as long as it hits the target, figuring they can call the bluff of the US and NATO not calling for a full-fledged war."

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