When Japan quietly deployed members of its elite airborne brigade for parachute drills in the Philippines’ northernmost province earlier this month, the exercise was not vigorously publicised by officials on either side. The drills on Batan Island, in the Batanes province, formed part of Kamandag – a countrywide mission jointly hosted by Philippine and US marines that ran until Wednesday. Involving some 2,000 troops, the exercise was designed to improve readiness, interoperability and...