Not all air rage is the fault of the passenger. I have observed this with my own eyes. I was on Delta 128 (ATL-DUB) on the 22d December. I was travelling with my wife in Business class. As we were approaching Dublin the FA announced that they were distributing landing cards as they "were required by the British special branch". I don't think she had the faintest idea of the implications of what she had just said or that Irish people might find her comment just a tad offensive. She then started arguing with several irate business class passengers about whether the cards were in fact needed. She seemed to be unaware that the republic of Ireland is a seperate country from the UK. She had a "full and frank exchange of views with forcefull opinions being expressed by both sides" with a man who my wife recognized as the head of a major irish government overseas trade organization. At no time to he physcially or verbally threaten her. On our arrival at the gate we were met by the police, who rapidly lost interest once they discovered how the incident started.
The point of all this is that creating blacklist databases or giving aircrew draconian powers has to be reconciled with the fact that they too are human beings and prone to mistakes of judgement. I observed staff of a highly reputable and respected US airline attempt to get a senior business figure arrested simply because he had reacted to what was by his standards extreme provocation. We have an existing legal system that is capable of handling situations like this. It tends not to get used as often as it should.
As for Alcohol - the time has come to stop the unlimited supplies of free beverages. one or two is fine but more than that is asking for trouble.
theRolfe