U.S.-Japan Defense Relations Under Trump

During the 2016 U.S. presidential contest, Donald Trump was highly critical of the structure and costs of the U.S.-Japan mutual defense relationship and openly raised the possibility of a Japanese nuclear deterrent. His remarks caused substantial confusion, concern, and consternation within Japan and among U.S. supporters of the U.S.–Japan alliance, which has more typically been described as anchoring stability in the Asia-Pacific and the cornerstone of the regional security architecture that the U.S. built up in Asia after World War II.

However, U.S.–Japan relations appear to be stabilizing in the wake of a highly successful visit by Defense Secretary James Mattis to Tokyo in early February that reaffirmed the alliance “for years to come,” and an equally successful visit by Prime Minister Shinzo Abe to the U.S. a week later.  Secretary of State Rex Tillerson, perhaps reflecting Mr. Trump’s recent promise to stand behind Japan “100 percent,” recently affirmed to his Japanese counterpart that the Trump administration will continue to apply Article 5 of the U.S.–Japan Mutual Security Treaty to the Japanese-administered Senkaku Islands. Mr. Trump appears to have concluded that the alliance with Japan is more important than his previous remarks suggested.