United States and Russia
Whatever Trump’s reason for the sabre-rattling deployment, strategic advantage is not one of them. Moving a pair of Ohio-class submarines equipped with nuclear missiles — “boomers” in US military parlance, or “bombers” in the UK — nearer to Russia would put them in shallower waters, making them easier to detect. And moving them anywhere quickly, which means making noise and disturbance in the water, would also increase their vulnerability."
