Putin seems like a guy who will try whatever he thinks he can get away with. I don't know what US capabilities are in Alaska, but I know we have basically no ability up there, and guys like Putin will take what they can easily walk away with. Look at China. You'd think no nation would have the gall to build some islands in the middle of the sea and then declare that their territory extends for two hundred miles all around them, practically up to the coastlines of neighboring countries, but they did and they are. Why? Because they can.