The possibility of Japan joining the alliance is now seriously discussed in Tokyo and the capitals of the Five Eyes members -- the United States, United Kingdom, Canada, Australia and New Zealand. Joining Five Eyes would signal Japan’s even deeper integration into US alliance structures, regionally and globally, and raise expectations for Japan to act as a fuller ally in all sorts of contingencies.
Japan’s greatest potential contribution to allies is probably in signals and imagery intelligence, especially vis-a-vis China.
The prime minister will avoid opening up a controversial foreign policy issue so close to a general election; his successor may be bolder.
Japan’s partners still run a risk of leaks due to Japan’s lag in cybersecurity and institutional arrangements, but this is decreasing.
