The Importance of Poetry
It's worth quoting an incident here: Minamoto Yoshiiye in the 11th Century defeated Abe Sadato at the 'Fort of Robes', and sent these lines to him: "Ah, your Fort of Robes / Is at last reduced to tatters!", and Sadato responded in renga style (see later in this section) with "What a pity! / Long usage has caused / The threads to wear out." This says something to me about the centrality of poetry to the Japanese soul.
I'm not sure how much trust to put in some writers' claims about just how big poetry is in Japan. Lesoualc'h says of the Hyakunin-isshu "Every Japanese must know the contents by heart." R. Sieffert, in La Literature Japonaise, says that the writing of haiku is "practised today by all Japanese, no matter what their education or social position." Frankly I don't believe either, but the fact that respectable commentators can say such a thing shows how different Japan is from any other country when it comes to poetry. Henderson shows that there are at least a million new haiku published in professional magazines each year, and over half a million tanka/waka - these are astounding figures, so maybe Sieffert isn't so far from the truth.