It’s been a tenet of diplomacy since Machiavelli that leaders do their most crucial work in private while the public are distracted elsewhere. So it was with Emmanuel Macron’s state visit to the Netherlands last week, which finally got down to the lucrative business of “chips” on day two. By then the French president had been mildly heckled by protesters questioning his democratic mandate for domestic pension reform, added to which he had made a charmingly cackhanded and widely tweeted attempt to speak Dutch after a royal banquet in his honour. In geopolitical terms he has also maintained his line...