The Korean peninsula has seen a spate of tension-raising military activity in September and October, most notably a North Korean ballistic missile flying over Japan and landing in the Pacific Ocean 3,200km off Japan's east coast. On Friday North Korea sent warplanes close to the border with the South and test-fired a short-range ballistic missile, the latest in a recent series of launches conducted at a pace not seen in recent years.

The missile that flew over Japan symbolises the current state of the decades-old North Korea crisis. The Democratic People's Republic of Korea (DPRK) is not only keeping its nuclear weapons, it is expanding and diversifying their delivery systems too. Pyongyang is attempting to leverage its growing capabilities to gain concessions from its adversaries.