A lot of commenters are mentioning that the distance is greater than the distance by sea -- but the difference isn't as much as you might think.
Look at the shortest route between LA and Beijing and you'll see that you already go over Siberia and the coast of Alaska. http://www.gcmap.com/map?P=LAX-PEK
Let me guess - some people don't understand cartographic projections? The shortest distance between two points is not a strait line on a map[1], especially when you are a long way from the equator.
Look at the shortest route between LA and Beijing and you'll see that you already go over Siberia and the coast of Alaska. http://www.gcmap.com/map?P=LAX-PEK