The threat to the U.S. mainland seems distant. Yet, tell that to American military and civilian interests in Guam, Hawaii and other Pacific Rim territories. Reports by international sources like Reuters confirm North Korea has moved ground assets into position to target U.S. territories in the Pacific.
On March 26, North Korea's KCNA news agency stated,
"From this moment, the Supreme Command of the Korean People's Army will be putting into combat duty posture No. 1 all field artillery units, including long-range artillery units and strategic rocket units, that will target all enemy objects in US invasionary bases on its mainland, Hawaii and Guam."
North Korea continues to experiment with long-range capabilities. Yes, North Korea's recent rocket attempts fell far short of reaching the U.S. mainland. However, if they continue to refine their rocket technology through trial and error, they will eventually achieve the distance and trajectory to hit the West coast.
The nuclear element. Remember, North Korea possesses nuclear weaponry. All they will need to do is perfect their rocket technology, then add a nuclear warhead.
Now, consider this. North Korea does have short and mid-range rocket capability. If they were to arm a mid-range rocket with a nuclear warhead, they could reach U.S. territories like Guam or hit a naval carrier group in the Pacific.
Analyze the capability and distance of North Korea's rocket technology...
U.S. Secretary of Defense Chuck Hagel announced in early March pre-cautions to avert a attack on the West coast. The announcement stated that several batteries of defensive counter weapons would be deployed at key locations to protect the coast. Similar rocket interceptor batteries have been used to defend Israel and were used for over a year in Washington, DC, following the 9/11 attack.
Again, we have a unstable, irrational leader calling the shots in North Korea. Kim Jon Un is a young maniacal version of his father. His inexperience combined with his hard core military leader's drive for dominance could be enough to tip North Korea and the United States into a full scale conflict.