Another of those ridiculous rows that bedevil relations between Washington and Tokyo has blown up, this time over the Computer Education Centre’s decision to use the educational variant of the Tron operating system – to be supplied by Matsushita Electric Industrial Co on an exclusive basis – on 700,000 computers to be procured for use in Japanese schools: the issue appears to be the decision to specify Tron for the schools system, for which IBM Japan and Nippon Unisys are among the 12 bidders building prototypes, on the grounds that it would tend to shut out the US software industry; the complaint looks suspiciously like a demand by the US that it should have a monopoly of the operating systems used in Japan, and while Apple Computer Inc feels disadvantaged over the decision to use Tron, NEC Corp, whose runaway market leader, the PC-9800 series, uses a version of MS-DOS, is no less disadvantaged.