I absolutely comprehend that. 

China isn't really building a "blue water" Navy. They have no bases to arm or fuel. Their ships all lack range. 

Yes, we need to up our shipbuilding capacity. We REALLY need to get off our asses and get a bunch of modern Frigates built and figure out the next generation Destroyers. 

The U.S. and it's allies already control Greenland. The U.S. can do anything there it wants. There currently is no security threat. Unless, of course, the current administration is planning on dismantling or dropping out of NATO.  THEN Greenland becomes important. The U.S. takes Greenland, Russia takes as much of Europe as it can, and you're back to "Great Power" politics which was so successful in the 18th and 19th and early 20th Century.