Anyone with a sense of history who has watched the fascinating new Ken Burns documentary on PBS, “The Roosevelts: An Intimate History,” may have experienced a sense of déjà vu during episode six, which chronicles the tumultuous events of 1939-44. That feeling of “we’ve been here before and we’re doing it again” comes from the pre-World War II years, when President Franklin D. Roosevelt focused virtually all his attention on domestic issues and little on foreign policy. It is eerily reminiscent of what is going on in the world today with President Barack Obama and his administration.