If it was such a simple argument then why do people have such dificulty understanding the limitations of their mind, body, desires etc? As someone pointed out earlier people should learn to live in moderation; it is one of the wisest ways to be.
Only making it illegal would lessen its dangers and consequences of its use; whether that be domestic violence, death by misadventure, drink-driving all of these are as likely with short-term long-term use (which was your original point).
This reminds me of the phrase "Guns don't kill people, people do" or something like that. Is that your line of thinking?!
However, I think a tangent has been found. Initially you stated: "That's not true of alcohol which itself only becomes dangerous through consistent abuse." and based on what I said previously I think that the facts are alcohol can be as danerous to first time users as long-term. It clouds the mind and ability to think whether you are trying it for the first time or the hundredth. Hence the unforseen consequences of a person using alcohol for the first time are limitless and can have unfortunate conclusions.