The content originally appeared on: CNN (CNN)Russia's invasion of its neighbor in Ukraine is the largest conventional military attack that's been seen since World War II, a senior US defense official said Thursday outlining US observations of the unfolding conflict. 'We haven't seen a conventional move like this, nation-state to nation-state, since World War II, certainly nothing on this size and scope and scale,' the official told reporters Thursday. 'And if it unfolds the way that hereto we have come […]