The first nationstate warfare took place between soldiers on the ground, and then ships at sea. In the 20th Century, the battles moved into the skies. On Thursday, the Justice Department claimed Iran had attacked U.S. infrastructure online, by infiltrating the computerized controls of a small dam 25 miles north of New York City, heralding a new way of war on American soil. “We can tell the world that hackers affiliated with the Iranian government attacked U.S. systems, and we seek to bring them to justice for their crimes,” Assistant Attorney General John P. Carlin said, unveiling charges against seven...