North Korea test-fired a pair of ballistic missiles with a potential range of striking Japan on Sunday, in a possible protest of Tokyo’s adoption of a new security strategy to push for more offensive footing against North Korea and China. The launches came two days after the North claimed to have performed a key test needed to build a more mobile, powerful intercontinental ballistic missile designed to strike the U.S. mainland. The two missiles traveled from the country’s northwest Tongchangri area about 500 kilometers (310 miles) at a maximum altitude of 550 kilometers (340 miles) before landing in the waters…