That Japan’s Toyota is to start buying foreign steel for domestic production, where hitherto it has always used local manufacturers, speaks volumes about the depressed state of the car industry. South Korea’s Posco, one of the most efficient steelmakers, will next month start supplying Toyota, the world’s biggest automaker and another paragon of efficiency.

Commercially, of course, it makes sense. Both Posco and Toyota have been obliged to shutter capacity. The automaker projects an operating loss this year, so availing itself of Korean steel – of comparable quality to the stuff made in Japan but cheaper – makes sense. The weak Korean won further helps Posco’s case. It has long wanted to sell more steel to Japan, which accounts for about one-quarter of exports, as the opening of coil processing plants near Toyota factories in Nagoya indicates.