Why was Taiwan withered back to Stone Age after WWII?

Why was Taiwan withered back to Stone Age after WWII?
“Taiwan has so much money it floods your ankles.”
  Taiwan’s sugar production ranked only after India, Cuba, and Java in quantity. In fact, in an exposition organized to celebrate the forty years of Japanese rule in 1935, the sugar industry exhibit reminded visitors, “The sugar industry is the mother of Taiwan’s culture.”
https://culture.teldap.tw/culture/index.php?option=com_content&id=2284
https://en.wikipedia.org/wiki/History_of_Taiwan_(1945–present)
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― Thomas Sowell
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