'Is the only solution' What arrogant words they are! They sound like a suzerain's voice. It is true that a foreign and security policy is a government's issue, but a construction of a military facility that has a huge effect on regional people's life is another problem. In the USA you can't build a military base without the consent of local residents.
The U.S. government should hear the Okinawan's voice and rethink the construction.