I think its decriminalization and eventual legalization will be a bit more long-tail, for precisely the political reasons you've suggested. The pre-boomer generation who brought us the prohibition is still an important voting demographic. Also, pro-legalization advocates tend to oversell the benefits while underselling the downsides. People operating machinery (including cars) are pretty much just as dangerous as drunks. People toking up at lunchtime will have serious productivity issues in the afternoon at work. Use among kids will likely go up. These things need to be addressed.