TURNABOUT: Japan helicopter carrier conducts operation to protect US ships.

This is a bigger deal than just a routine escort mission:

The MSDF helicopter carrier Izumo left the U.S. Navy base in Yokosuka, Kanagawa Prefecture, southwest of Tokyo, on Monday morning. The mission, ordered by Defense Minister Tomomi Inada, is aimed at deterring the North Korean regime, which attempted to test fire a ballistic missile on Saturday, from further provocations by demonstrating a robust U.S.-Japan alliance.

The carrier is scheduled to join a U.S. supply vessel in the Pacific on Monday and escort it on its journey to waters off the island of Shikoku in western Japan.

Under the new legislation, Japan’s SDF can provide protection for U.S. forces in ordinary times using a limited, minimum number of weapons to the extent needed to carry out a mission.

Today’s mission shows that Japan’s attitude towards the military has moved far away from its postwar constitutionally mandated pacifism, and towards something more assertive.

What the report left unsaid is that while the Izumo and her sister ship Kaga are classed as “helicopter destroyers,” they could conceivably carry and launch F-35B VTOL fighters — which would put Japan back in the power-projection business for the first time since 1945. Only this time, hand-in-hand with the U.S. Navy.

Beijing, which had previously protested that the Izumo is an “aircraft-carrier in disguise,” is on notice.