It's sad the people still have this breakdown in logic and their emotions overwhelm them when it comes to "seriously dangerous" drugs like heroin or crack. Just what part of the problem with these drugs do you think is ameliorated by prohibition? If anything, it's even more critical that these drugs are legalized:
-Cocaine and heroin represent the vast majority of global organized crime and related violence. The exact same points about never stopping other substances apply even harder here. Doesn't matter how "bad" the drugs are, you're never ever going to stop global organized crime from reaping billions upon billions of dollars through prohibition.
-Locally, it's these drugs that are responsible for the large majority of secondary crimes against non-involved parties, such as robbery and property crimes, to fund addictions. People aren't robbing and stealing for their pot or MDMA habits, which I assume aren't "really" hard by your standards. These crimes aren't committed because of the drugs inherent biological response pattern in an addict (unlike alcohol, which DOES make violent behavior more likely), they're committed because prohibition results in a cost structure that puts maintaining a habit very difficult without wealth or crime. Alcohol and cigarettes are cause dependence just as strong in an addict, and I guarantee if an addiction to those cost hundreds of dollars per day, you'd see the exact same related violence.
-Even when it comes to "really hard" drugs, there's simply no evidence that legalization would lead to increased addiction, because do you really think there's thousands and thousands of people just waiting to go out and get addicted to heroin if only it were available from a doctor or pharmacist? It's legal to possess all drugs in Portugal, and they have no such usage spike. When you redirect money towards education and treatment and provide an environment where there's no fear of arrest for admitting you're a user, usage rates actually drop.
-With the financial and other aspects of acquisition, addicts are unable to hold jobs for a variety of reasons, and as heroin maintenance programs in other countries have shown, a steady cheap legal supply returns these people to functional, contributing members of society that can hold down jobs. And obviously there's health benefits associated with a legal pharmaceutical supply like OD prevention the most well known.
-People like to talk about "the children"... what kind of world do you want for yours if they wind up experimenting? A felony where getting caught twice or violating probation requirements means a lifetime of stigma. Interacting with dangerous criminal gangs to get an unknown product. Prison. Stigma attached to getting help. There is ZERO evidence that if we just crack down harder we're suddenly going to win the war on drugs and heroin, meth, and coke will vanish from the world, so no matter how much you wish that were the case, you're stuck with the reality that drugs are everywhere and kids experiment. If my kids made that mistake, I'd want them to get a safe product from a medical professional and be provided with non-abstinence-based education and have stigma-free access to well funded help and not be labeled a criminal and tossed into a cage and branded for life if they get caught. What do you want for yours? "a drug free world" is NOT an option.