Thursday marks the 75th anniversary of D-Day, the allied invasion of the Nazi’s so-called Fortress Europe during World War II. Thursday marks the 75th anniversary of D-Day, the allied invasion of the Nazi’s so-called Fortress Europe during World War II. These lessons—that problems left to fester over there do not get better but come to haunt us over here, that the world is safer when the United States builds and wisely wields a military capacity commensurate with its resources, that U.S. interests are best served by leading a coalition of allies and partners in concert rather than retreating to a cramped and short-term vision of parochial nationalism—were hard-learned but have gone out of fashion in the academy and in many political corners as well.