Never heard of great-circle routes? Just a reminder that the Earth is roughly spherical and not a flat projection as on a map. A globe and a piece of string are all you need to comprehend the concept that the shortest distance between two widely separated points on a spherical surface doesn't conform to cardinal directions on a map unless one point is directly north or south of the other. For example, we may think of Russia as lying east or west of us, depending on whether we live closer to either our east or west coast, but the shortest distance between Russia and the US is over the Arctic Ocean. That's why our early warning system to detect unfriendly missile launches is located in the far north of our continent and in Greenland (which, tectonically speaking, is also a part of North America).
