There's something to be said for national isolation. Peace, for example. The very few foreigners allowed into Japan during its 250-odd years of almost total seclusion, from the early 17th century to the mid-19th, were awed by the spectacle of a nation permanently at peace.

In Europe, this was inconceivable. "There is not one such peaceful country anywhere in the world," said the head of the Dutch trading station on Deshima Island off Nagasaki in 1838. "In the West, one cannot sleep or eat in peace a single day."

Yes, peace — but could it last? As the 19th century dawned, Japan, static in an increasingly dynamic world, began to foresee challenges it might not be able to meet. Foreign ships — British, Russian, American — were infiltrating its waters, docking in its ports, clamoring for trade, demanding supplies. An early Japanese response was the uchiharai edict of 1825: all approaching foreign ships, regardless of nationality, were to be driven off with gunfire. Which was all very well — but Japanese guns, as soon became evident, were no match for Western ones.