Modern Japanese gendai (現代) haiku are increasingly unlikely to follow the tradition of 17 on or to take nature as their subject, but the use of juxtaposition continues to be honoured in both traditional haiku and gendai.
There is a common, although relatively recent, perception that the
images juxtaposed must be directly observed everyday objects or
occurrences.
http://gendaigallery.org/content/about-gendai