There are three stages needed to deal with the problem.
Your three stages are once again only dealing with the symptoms not the cause. This problem is going to go away until a stable government of sorts is 'installed' in Somalia which can police its own waters and apprehend any individuals engaged in piracy. Since the international community will have no appetite for this after their last disastrous involvement in the country, perhaps we could persuade a private military company to take on this challenge? Any takers? Blackwater?