In Japan, so often the center of mobile industry innovation, the challenges of the 5G era are exemplified. The three MNOs – NTT Docomo, KDDI and Softbank – are known for technical innovation but exist in a saturated, over-regulated market, and now have to cope with the imminent entry of a newcomer, ecommerce giant Rakuten, which plans to build on its existing MVNO business now it has secured its own spectrum. Rakuten is the epitome of the modern digital operators which could shake up this industry in the 2020s (Reliance Jio of India being another). It has a significant digital services business based on ecommerce and payments. It can leverage its own 4G network to expand the mobile aspects of…