TOKYO - Japan is to acquire medium-range, air-launched cruise missiles, capable of striking North Korea, a controversial purchase of what will become the longest-range munitions of a country that has renounced the right to wage war.Defence Minister Itsunori Onodera did not refer to North Korea when announcing the planned acquisition and said the new missiles would be for defence, with Japan still relying on the United States to strike any enemy bases."We are planning to introduce the JSM (Joint Strike Missile) that will be mounted on the F-35A (stealth fighter) as 'stand-off' missiles that can be fired beyond the range of enemy threats," Onodera told a news conference.Japan is also looking to mount Lockheed Martin Corp's extended-range Joint Air-to-Surface Standoff Missile (JASSM-ER) on its F-15 fighters, he said.