Welcome back, Japan, to the normal economic world. The Bank of Japan’s decision last Friday to raise its main interest rate from zero to 0.25 per cent gives the central bank the choice, for the first time in six years, of next cutting or raising rates, just like its peers in the US, the eurozone and the UK.

Not that anyone is expecting the bank to loosen policy. Quite the opposite. For Japan, the end of zero interest rates signals that a “lost decade” of falling asset prices and deflation is well and truly behind it. But for nervous international investors, the main question is whether Japan’s return to modest economic expansion and monetary orthodoxy could expose the fragility of unsustainably large global trade imbalances.