What is their rationale? We have alcohol and nobody believes that should be illegal. If one is for freedom and liberty one is supportive of legalization.
The problem is, it ruins families, wrecks lives, and makes people stupid. Every single idiot I have ever run into, has been a pot head.
Additionally, THC is well known to cause birth problems, including learning disabilities, or low birth weight.
Lastly, work ethic and performance, are greatly impaired. 55% more accidents, more injuries, 75% higher rates of absenteeism. Higher job turn over.
This all matches my experience in the work place.
Additionally, on a purely economic standpoint, drugs have zero economic benefit.
When you produce say, iron ore, that iron ore has an economic benefit. That production has value, which grows the economy. The iron can be turned into other products, like steel, which can be turned into other products like beams, which can be turned into other products like buildings, bridges, or cars or on and on and on.
These are productive industries that build value in the economy, which in turn produce more jobs, and more value, and more products.
Pot, like gambling, produces nothing. It's poor people, paying rich people, to consume something that produces no value.