Flouride was added to water to prevent Dental Caries, so was probably added to help sell the vast quantities of High Fructose Corn Syrup, phosphoric and citric acid used in the North American diet without everyones teeth rotting out.

As for the hard core commie conspiracy the little blue pill so popular with American organised crime Spammers (no doubt working tirelessly for the Pharma companies) is the modern day antidote.