Who doesn't love haiku? It is not only America's most popular cultural import from Japan but also our most popular poetic form: instantly recognizable, more mobile than a sonnet, loved for its simplicity and compression, as well as its ease of composition. Haiku is an ancient literary form seemingly made for the Twittersphere--Jack Kerouac and Langston Hughes wrote them, Ezra Pound and the Imagists were inspired by them, Hallmark's made millions...