OPINION When North Korea late last month rained rockets on Yeonpyeong island, near its border with South Korea, the term ‘sabre rattling’ took on new meaning. It’s not as if petulant children or angry protestors were yanking at the neighbour’s wire-fence.

Nor were North Korea’s rockets a subtle message to its southern brethren. They were, at first blush, aggression of the war kind. Yet closer scrutiny of footage and all the posturing and analyses suggest that this was managed aggression. What’s behind it?