If it was then it wouldn't be so much more prevalent and widely available. Any argument made against cannabis, a federally illegal drug, because it causes harm should be triply made so against alcohol, a legal drug that has annihilated many more millions of lives than cannabis ever has or will.

I'm saying if you're (generic "you") checking for damage to try to make a case against it, you should be investigating a lot of other, worse stuff, not this.