pirates have proved increasingly mobile and flexible in their tactics

The Ministry has taken the decision after noting that about 35 per cent of merchant ships transiting through pirate-infested waters deploy armed security guards and that the pirates generally do not attack ships with guards on board.
... ultimately the problem of Somali piracy can be solved only on land. That will take time. In the absence of a functioning Somali state, a better co-ordinated international naval force and patrolling larger stretches of water are becoming necessary.