Reading these anthologies of English-language haiku (some in Scotch, too), I was reminded of a recent scandal in Japan. The association of "traditional" haiku writers, Haijin Kyokai, asked publishers not to allow "nontraditional" haiku in the school textbooks they print! The world of English-language haiku may never witness such a spectacle.
The reasons are relatively simple.
In English haiku, the distinction between traditional and nontraditional is hard to delineate. The two elements that make Japanese haiku "traditional" are, as everyone knows, the so-called "yukiteikei": the inclusion of seasonal references ("kigo") and the preservation of the 5-7-5 or 17-syllable form.