Japanese and U.S. Marines conducted their first airborne landing and combat drills together on Tuesday, indicating a deepening of military cooperation in the wake of increased military assertiveness by China and Russia. The drills held near Mount Fuji were part of a three-week joint exercise, which involved about 400 troops from Japan’s Amphibious Rapid Development Brigade and 600 troops from the U.S. Marines based in Okinawa. Tilt-rotor Ospreys transported the brigade during the drills. “We are committed to securing the peace and stability in the region through Japan-U.S. joint responses. Any potential adversary will see this as our actual capability, not just words,” Col. Masashi Hiraki, commander of Japan’s Amphibious Rapid Development Brigade, said. Col. Michael Nakonieczny, a commanding officer of the 31st Marine Expeditionary Unit based in Okinawa, said that the troops are “operating across all domains to achieve the effects that are required to be successful” on the …