The make-pot-legal-and-tax-it argument doesn't fly. All taxes are a dead weight loss, and it's bad policy to argue something should be legal to tax it. You can argue the lost productivity of people who go to prison because pot is illegal, you can argue the potential of jobs created if pot were legalized, you can argue the possibility that crime would be reduced, prison populations would decrease and the costs of running prisons would go down.
But you can't argue the legalize and tax it, because that's stupid.
Worse, you can't argue taxing anything to save social security, because saving social security is also stupid. Pay the folks who are 50 and older what they've been promised, then let the rest of us sink or swim.
We should:
1. Legalize the illegals, so they can pay social security.
2. Get rid of the income tax.
3. Legalize the drugs so our law enforcement can concentrate on keeping the new influx of illegals out of here.
4. Get rid of personal property tax.
5. Free oil from Iraq for everyone.
6. And lastly give every citizen 10 acres of land.