On May 10, the Japanese government offered an inconsistent response to North Korea’s ballistic missile launch the day before (May 9). This is because the administration, urged by the U.S., avoided language saying “the projectiles were ballistic missiles.” After the U.S. government announced that they were ballistic missiles, Tokyo hastily fell in step with the U.S. The government also swiftly filed a protest with North Korea. However, even after the announcement by the U.S., the administration repeatedly said, “We are in the middle of analyzing the launch.” This indicates that Tokyo was unable to predict how the U.S. would respond to the missile launch and was at the mercy of Washington.

According to a source familiar with Japan-U.S. relations, the U.S. notified Japan as early as May 8 of Washington’s view that the projectiles that North Korea had fired on May 4 were ballistic missiles. At the same time, the U.S. urged Japan to refrain from making an announcement on the launch and to say, “[We are] in the middle of analyzing [the launch]” in consideration for President Donald Trump’s intention to avoid an adverse effect on the U.S.-North Korea negotiations. Under the circumstances, following North Korea’s other launch on May 9, the Japanese government anticipated that “the U.S. will not announce that the projectiles fired on May 9 are ballistic missiles,” according a source connected with the government.

The Japanese government was, therefore, caught off guard when the U.S. announced on May 9 (EST; May 10 JST) [that they were ballistic missiles.].