Nearly three months after lifting its long-standing arms embargo, Japan recently approved plans to supply missile parts to the U.S. and conduct joint military research with a British company. Behind the scenes, however, there was a deal that fell through.

Under new guidelines governing the transfer of defense equipment and technology, Prime Minister Shinzo Abe on July 17 convened the National Security Council to look into two applications submitted by private companies.

One was Mitsubishi Heavy Industries’ request for permission to export seeker gyros used in Patriot surface-to-air missiles to the U.S. The other involved Mitsubishi Electric, which was seeking approval for joint study with U.K. missile maker MBDA to boost the accuracy of Meteor missiles for use in the F-35 stealth fighter. […]