<h1>Constitutional constraints on military deployment limit Japan's warship commitments, shaping talks on security and defence cooperation.</h1> Japan declined to commit warships in response to US requests, citing constitutional constraints, legal questions over the US action, and public opposition; limited non combat missions such as survey, intelligence, or minesweeping are possible only after a ceasefire and with domestic legal authorization. Concurrently, Tokyo is revising defence policy to accelerate long range missile deployment, consider joining a US multi layer missile defence system, and lift the lethal arms exports ban to bolster defence industry cooperation, while pursuing energy and rare earth investment projects to diversify supplies.