Cannabis is detrimental to your mental health, Agree. But,...

Cannabis is detrimental to your mental health, Agree.

But, medical marijuana eliminates most of the THC (which can cause anxiety and mental health issues) from the plant only leaving mostly the CBD oil. Some THC is left in when treating cancer patients as it alleviates depression and increases the appetite.

Trump is very aware of the opioid epidemic in the States caused by
over prescribing by doctors along with being pushed by the big pharmaceutical companies.
When their doctor refuses to supply more due to the addictive nature
of the drug that’s when many go on to heroin. To alleviate the
withdrawals from the opioids.

Trump is backing medical marijuana because of the above.
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Is Marijuana the key to overcoming the opioid crisis?

https://www.menshealth.com/health/a19607404/marijuana-drug-addiction-cbd-opioid-cocaine-use/