Lyric discussion by thepriceiswrong. 

considering this song was first performed in 1961, i highly doubt the vietnam reference. Also, this song was originally a 1959 poem by Leonard Lipton, who then gave Peter Yarrow his lyrics who proceeded to make it into a song. I also highly doubt it is a marijuana reference because Leonard lipton based his poem on the Ogden Nash poem, "The Tale of the Custard dragon" (eecs.harvard.edu/~keith/poems/Custard.html) which is cleary not a marijuana reference.

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