South Korea and Japan have reported that North Korea has fired an intercontinental ballistic missile, recording the longest flight ever before falling into nearby east coast waters. After observing the launch, Kim Jong-un took to state media to warn Pyongyang’s international opponents of their willingness to respond to threats and take “appropriate military action”. The North Korean leader went on to affirm that his country “will never change its line of bolstering up its nuclear forces.” The ICBM flew for roughly 86 minutes and was reportedly fired at a steep angle, according to Japanese Defe…