It is no surprise that North Korea tested its sixth nuclear device, and in response, calls are growing in South Korea for consideration, or the actual development, of nuclear weapons. Considering the growing threat presented by Pyongyang's development of weapons of mass destruction, this should also come as no surprise.

However, what is surprising is that this option is not being formally considered by both South Korea and the United States, all the more unusual considering U.S. Secretary of Defense Mattis having mentioned that President Trump wanted a briefing on all military options. A nuclear deterrent for South Korea was, apparently, not on that list.