At their late-August summit, former Prime Minister Shigeru Ishiba and Indian Prime Minister Narendra Modi adopted a suite of documents signaling their nations¡¯ intent to increase cooperation across security and economic domains. Chief among these was the ¡°Japan-India Joint Vision for the Next Decade,¡± a by the two leaders outlining a 10-year roadmap for bilateral cooperation.

Yet this agreement comes at a moment of heightened uncertainty for India. Since May, New Delhi¡¯s relations with Washington have deteriorated sharply, eroding India¡¯s international position and placing unprecedented strain on ¡°the Quad,¡± a diplomatic partnership between Japan, India, Australia and the U.S. committed to fostering a free and open Indo-Pacific.

The once-routine Quad leaders¡¯ summit in New Delhi, planned for this autumn, wasn¡¯t held ¡ª raising fundamental questions about how a ¡°half-cracked¡± Quad will shape Japan-India defense cooperation in the decade ahead and how Tokyo should respond.