(Editor’s note: this story was updated on June 23 to clarify that the SDA experiments consist of four satellites and a single payload and to add new information provided by SDA about the cost of the projects.) The U.S. military has readied for launch this week four small satellites and a payload designed to validate technologies pivotal to a new National Defense Space Architecture underpinned by a future proliferated low-earth orbit constellation, new capabilities that will experiment with space-based laser...