PAOAY, Philippines—Right on cue, the missiles blazed from their launcher, kicking up sand behind them. A few minutes later, cheers from the VIP pavilion confirmed that the Japanese Type 88s had hit their target, sinking a decommissioned Philippine ship about 46 miles away. Last week’s mock attack marked the first time Japan has fired the missile outside its own borders. Part of the annual Balikatan exercise, it came just two days after Japanese …