The Army’s 1st Multidomain Task Force, the first of a new unit that will field hypersonic and ship-killing missiles, deliberately shares less information about itself than other military units, according to its commander. These measures, which include not having a website or social media accounts, contribute to operational security, Brig. Gen. Jim Isenhower, the commander, said May 19 at an Association of the U.S. Army conference on land forces in the Pacific. “In many ways, our formation has kind of...