Legalizing Marijuana

There's a vigorous comment string on The Volokh Conspiracy on legalizing pot in the U.S.A.

Here's mine:

I can think of several likely consequences for legalizing MJ in the USA:

1) The price of MJ in the USA would drop drastically.
2) There would be thousands of Americans freed from jail.
3) Spending on law-enforcement, courts and prisons could be re-directed to treatment and rehabilitation.
4) Thousands of young men would no longer be able to make a living as street dealers.
5) Mexican drug cartels would find that there is no profit to smuggling MJ into the USA.
6) Americans would try to smuggle MJ from the US (where it is cheap and legal) into Mexico and Canada (where it is illegal and expensive).
7) Monsanto would create a genetically-modified MJ ("Roundup-tolerant") and patent it.
8) Some users of other drugs (cocaine, meth, etc.) would switch to MJ because it gave them a similar experience but was cheap and legal.
9) Pigs would fly.