NATO has faced tensions, and even hostile fire, between members before. But the crisis unleashed by Donald Trump’s drive to acquire Greenland is unprecedented, turning NATO’s indispensable member against most of the rest. Mr Trump’s announcement of tariffs against countries that have stood with Denmark and Greenland on Saturday was an escalation that could permanently damage what is justifiably called history’s most successful alliance.

The president has unleashed other turmoil besides the geopolitical kind. His attacks on the independence of the Federal Reserve, and the persistence of budget deficits as far as the eye can see, should normally spook lenders. So why aren’t bond-market vigilantes punishing America?