Is Japan’s sudden decision to halt planned deployments of Aegis Ashore — an advanced, U.S.-made missile defense system — a setback or calculated retreat?

As challenges continue to roil the project and cost-sharing negotiations with Washington loom, observers say the move, attributed by Defense Minister Taro Kono to technical and cost issues, could also be part of a gamble by Tokyo as it recalibrates its defense posture amid a changed security environment.

On Monday evening, Kono cited difficulties in ensuring rocket boosters from the interceptor missiles would fall in areas that did not put lives or property at risk, given current software and hardware issues.