Why was Marijuana Made Illegal?

For sometime marijuana was legal. It has a lot of good uses, other then just getting high and having a good time. It’s because of the negative effects it has on ones brain and mind. You would be totally under the control of the marijuana plant. Not thinking for yourself and making bad judgment, when you are under the influence of it. So around the early nineteen hundreds. A law was passed to make this substance illegal. Making a lot of people run to the border.