Portugal did NOT legalize drugs. They changed personal use and possession of less than a 10 days personal supply so that these were no longer criminal offenses. They become administrative offenses.
Producing, distributing, and selling remain criminal offenses.
In too much of an indignant hurry in my reply. Yes, it was decriminalization not legalization. But the point stands that reducing impediments to drug use isn't going to cause civilization to crumble.
Anybody who brings up the issue of the damage done to society by drug use has to then take into account the damage done by drug prohibition. It's clear (to many) that the latter is far more harmful.
Producing, distributing, and selling remain criminal offenses.