Domestic missile tests are essential for military readiness. Unlike live-fire exercises abroad, training on home soil allows more soldiers to gain experience using advanced weapon systems at a fraction of the cost of using foreign facilities. In doing so, the tests maintain Japan's ability to defend its territory, which is especially important given the fraught security environment.
Rather than missiles, Japan should prioritize diplomacy to secure its interests in the Pacific. By carrying out missile testing, Japan is engaging in an arms race that ironically makes the country more of a target for foreign aggression rather than less. It would be wiser for Japan to focus its efforts on preventing conflict by playing its part in defusing Indo-Pacific tensions.