I have relatives in the U.S. Navy Reserve, and they’ve been told to prepare to ship out for Japan. They thought it’s to help with disaster relief but now it looks like it might be to evacuate U.S. military personnel and their families.
The U.S. Pacific Command has been making plans for mandatory evacuations, just in case. If things got bad enough they would use large military air transports (C-17, C-5) to fly out as many personnel and families as they could, as fast as they could.
Currently the evacuations of military families are voluntary. On Saturday 230 people voluntarily left, on Monday 154 people left Japan.