The U.S. government faces a dilemma. Starlink, a private satellite venture devised and controlled by Elon Musk, offers capabilities that no government or other company can match. Its innovations are the fruit of Musk’s drive and ambitions. But they have become enmeshed with American foreign and national-security policy, and Musk is widely seen as an erratic leader who can’t be trusted with the country’s security needs. In other words, the United States has urgent uses for Starlink’s technology—but not for the freewheeling foreign-policy impulses of its creator. The conundrum is substantially new for Washington. During World War I, wealthy industrialists, such as Henry Ford and J. P. Morgan, poured considerable resources into the American war effort: Ford’s factories produced boats, trucks, and artillery for military use; Morgan lent money. After the war, John D. Rockefeller Jr. funded the League of Nations. But Musk is doing something different. He supplies his product directly to foreign countries, and he retains personal control over which countries can obtain his equipment and how they can use it. That discretion …