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A commercial ­dispute breaks out in the South Atlantic. ­Argentina asserts a hoary claim to the Falklands and takes it to the UN. Britain says push off, you must be joking. Nobody takes it ­seriously as war is inconceivable. ­Downing Street is more concerned with domestic unpopularity.

That was in March 1982. It was also last week. Then the tabloids greeted Argentina's claim with Stick It Up Your Junta. Now they are equally nuanced, calling the Argentine president, Cristina Kirchner, Queen Argie Bargy and Old Plastic Face. Then it took nine weeks of counter-invasion, with 1,000 deaths and £3bn spent, for Britain to restore the status quo ante. The Falklands war was a catastrophic failure of diplomacy and deterrence. Now, at least, war is unlikely.

Britain has almost...