It is quiet on the Korean peninsula, almost too quiet. Some 10 months have elapsed since Barack Obama was woken up at 3.55am to be told that North Korea was firing at a South Korean island, raising tensions on the peninsula to their highest level in years. That makes it 11 months since Pyongyang revealed it was pursuing a second nuclear programme based on uranium enrichment and 18 months since North Korean submarines torpedoed a South Korean naval ship, killing 46 sailors.

The length of time is important. According to Victor Cha at the Center for Strategic and International Studies, the average time it has taken Washington to

re-engage with Pyongyang following a provocation of this type is 5.4 months. The fear is that, if diplomacy drifts, Pyongyang will feel compelled to launch another military stunt to grab Washington’s attention.