In this remarkable book, Toshiaki Komura has discovered a poetic genre hiding, like Poe’s purloined letter, in plain sight. “Lost loss” is a perfect way of naming that elusive sense of loss at the equivocal core of some of the most compelling American poems, from Wallace Stevens to the poetic “first responders” of 9/11. We may have thought we knew what poetic elegies were all about. Komura makes us think again.