"It is incumbent on us to assume that North Korea today can range the United States with an ICBM carrying a nuclear warhead." - James Syring, Vice Admiral, Head of US Missile Defense, June 7th 2017.

"Trump blustered early this year that the DPRK’s final access to a nuclear weapon that can reach the U.S. mainland will never happen, but the strategic weapons tests conducted by the DPRK have clearly proved that the time of its ICBM test is not a long way off at all.” - Rodong Sinmun newspaper, North Korea, June 11th 2017.

If it's the KN-08 they are about to test, with a estimated range of 11,000+ kilometers (enough to hit New York or DC), and it's successful, we may be witnessing the beginning of the actions that lead to WW3.