9,000 U.S. marines to leave Okinawa

The story is at The Guardian:

By shifting a large number of the 19,000 marines on Okinawa, leaders in Tokyo and Washington said they hoped to reduce the US military footprint on the island while retaining a strong enough presence to deal with security emergencies in the region.

In a joint statement, the US defence secretary, Leon Panetta, and the secretary of state, Hillary Clinton, said the agreement would honour Washington's commitment to defending Japan and maintaining stability in an "increasingly uncertain security environment".

I will quickly admit to limited knowledge of military history and strategy, but I have never understood why so many American troops still have to be stationed in Japan to fulfill a WWII-era commitment.

Will this decrease the military budget?  Apparently not, because rather than returning to the U.S. or leaving the service, they are just being deployed elsewhere:

Up to 5,000 troops... will be sent to Guam, according to a US defence official quoted by Associated Press in Washington. The remainder will move to Hawaii or rotate between Australia and other parts of the region.