“Dear John” letters have loomed large in American war-lore ever since GIs first coined the phrase in World War II. Receiving a break-up note from a wife, fiancée, or girlfriend has come to appear a rite of passage for men in uniform. The motif of female treachery and male tragedy circulates both in the stories servicemen and veterans tell one another and in US culture more broadly – in pop music, movies, and novels. Yet no prior author has devoted a book to the “Dear John” phenomenon. That virtually no bona fide specimens exist in archival collections helps explain this lacuna. But the fact that so many “Dear Johns” were physically destroyed soon after receipt doesn‘t make these letters impossible to study. Instead of regarding Dear Johns as a female-authored epistolary genre, we should conceive these letters as the product of a male vernacular tradition. Men have told us most of what we know about how and why women composed these letters, and the effects they‘ve had on recipients. This book explores the interplay between letter-writing and story-telling, inviting readers to contemplate why love is so hard to sustain in wartime.