Wow - what a horrible situation. It sounds like you did everything you could reasonably think of, and it's unfortunate the purser would not do more.

This is where today's security environment can work in one's favor. When raising the issue to the purser, I would emphasize that this man is a threat to the safety of the aircraft & passengers. By being adamant, and possibly ensuring the 'story' contains unusual and disruptive behaviour, you will have gotten their attention. Trust me - cabin crew on US-based airlines today are far more paranoid than most passengers. Work this in your favor!

For another angle, which I have tried on one recent occasion very succesfully, appeal to their sense of professionalism. I had a situation where I simply appraoched the purser discreetly and said "this is not the kind of atmosphere your airline expects in a premium cabin, and that behavior really must stop". It was not an obnoxious drunk, but was just as bad - teenagers! Try it - it resolves the problem and you remain on the high-ground.

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- Bob