The U.S. Navy’s nuclear-powered submarine Ohio made yesterday a port call at the U.S. naval base in Yokosuka, Kanagawa Prefecture, mainly to allow its 155 crewmembers to rest. This is the first time for a submarine that can carry 150 cruise missiles and can dispatch special-operations troops to enter a Japanese port.

The 18,750-ton Ohio was commissioned in 1981. It was re-commissioned in 2006 after undergoing remodeling due to the post-Cold War nuclear reduction and the U.S. military’s strategic shift for the war on terror.

It is difficult to distinguish the Ohio, which used to be a ballistic missile submarine for launching nuclear missiles, from a vessel carrying nuclear weapons. For this reason, there is concern that it will irritate neighboring counties.