Japan's upper house election seems set to rehash a decades-old debate on consumption tax, says Gearoid Reidy for Bloomberg Opinion. TOKYO: Japan is facing a changing world of tariffs , artificial intelligence, and a potentially existential threat to its number one export. Yet its approaching election seems set to be dominated by a rehash of a decades-old debate. Consumption tax, first introduced in 1989 and raised over the years to its current maximum rate of 10 per cent, is shaping up to be