Japanese and US Marines had their first airborne landing and combat training together on Tuesday near Mt. Fuji as the two allies strengthen military cooperation amid growing maritime activity by China and Russia in the regional seas.Japan has been expanding its defence budget and capability for about a decade and is now revising its key national security strategy in the face of threats from China, North Korea and now Russia.On Tuesday, 400 troops from Japan’s Amphibious Rapid Deployment Brigade…