Berlin has too much [history].” Sinclair McKay cites this rueful observation in the preface to his new book about the city. Given that he is not simply discussing Berlin between the wars, or during the second of those wars, or in the Cold War that followed, but all of it, this may come off as a cry for help. History may — in those words attributed to, well, take your pick — be “one damned thing after another,” but when it came to Berlin, those things hurtled through time in a horde, colliding, overlapping and refusing to form an orderly line. And, in Berlin’s case, they had a way of mattering. Not for nothing does this book’s subtitle refer to Berlin as “the city at the center of the world.” Bad news for a writer aiming, presumably, at a degree of concision.