Fiery_penguin_of_doom wrote...
A major problem when dealing with pirates is the fact that they are in international waters. Who would be assigned the task to deal with them since no country has jurisdiction in international water. Another problem is the fact that most trade routes can't be avoided (like the ones near Somalia, Indonesia/Malaysia, Mediterranean). The third problem is corrupt governments who may be turning a blind eyes or worse, assisting in the pirating themselves. Somebody correct me if I am wrong but, I vaguely remember an incident where a military ship was moonlighting as a pirate ship. They boarded the target vessel acting as if they were going to search for drugs, and other things then they took over the ship and murdered the crew and passengers but, I can't confirm this so somebody back me up.
Another problem is that no international treaties or agreements allow for third parties to chase pirates into another country. Currently, the only thing the third party can do is chase them to the sovereign water while telling the other country who has jurisdiction in that area about the pirates themselves. This in turn has another problem, most pirate ships can easily vanish on coast lines since pirates don't really travel that far out to see.
Records say that only an estimated 1% of pirates are ever caught which only serves to encourage piracy since there is little risk and large reward. Some pirates are young kids such as the one who was captured by the American military. Which leaves the question of what to do with them once we catch them?
For all the reasons you said, in general, the navies of powerful countries have had a very difficult time fighting pirates, especially when trying to use traditional ships, like destroyers. Personally, I think we could do more to arm merchant ships, but ultimately, the problem is only going to seriously be alleviated when the Somalian government actually gains the power to enforce its own laws, or else the economy changes such that piracy is no longer as effective or necessary.