The highly erratic conduct of North Korean leader Kim Jong-un is usually as much a source of general bemusement as it is a cause for genuine concern.

When, for example, reports first surfaced a couple of years ago that the country’s defence minister had, on Kim’s orders, been publicly executed by anti-aircraft fire for falling asleep at military briefings, the temptation was dismiss them as black propaganda designed to undermine Kim’s dictatorship.

But the latest outrages committed by Pyongyang’s dysfunctional leader mean that we must dismiss any remaining doubts about how much of a threat his regime poses to the outside world.

Kim’s involvement in the murder of his half-brother, Kim Jong-nam, poisoned at Kuala Lumpur airport last month with a nerve agent classified as a weapon of mass destruction, illustrates the extreme lengths to which Kim is prepared to go to silence his critics. Since obliterating that minister in 2015, Kim is said to have executed others using flame-throwers, mortar rounds and packs of wild dogs. Only last week another five officials were said to have been executed using anti-aircraft rounds.