I have read this theory, and I can add there are many applications to hemp that have been taken by petroleum derivatives. See here I am getting ? The american economy is an oil based economy, not only to run cars, but to make plastics like nylon and polyethylene. Big business does not like people to use a natural ressource that they can grow in their garden. Dupont conspired at demonizing hemp to free the market for its Nylon.
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Aurel