I can think of no other old-time saying than, "drastic times call for drastic measures". If I were communicating with a resident in my neighborhood, such as Mr. Duterte, and something of this nature was said, with clearly threatening gestures - I would feel threatened. I speak indicating a lone person in an neighborhood, it says volume when a President says it. I believe this tactic will work.
While many political leaders rely on careful deliberation and shielded tactics, President Duterte addresses the terrorist Abu Sayyaf group directly. His actions and words may be seen as brash and provocative, endangering the citizens of the Philippines, but they are akin to his nature. Duterte, with a great deal of help and consideration, can defeat the terrorist group. His aggressive stance, however, might prove detrimental and eventually devastating for his own people. His attitude of non-negotiation and fearlessness is admirable, but the choices he makes alongside his bravado will dictate his success and safety.
Duterte's tough talk became more than just words shortly after he began his presidency. His war on drugs has so far resulted in more than 700 people killed in confrontations with police, while the number of arrests reached more than 7,600 in July. Impossible to see Obama or even GW using this type language to counter ISIS but it sure puts fear into those that harbor, feed and do business with barbarian devils like ISIS.
President Duterte can defeat the Abu Sayyaf Group, but he is going to need help. His military isn't very strong, and it is hard to tell at this point if parts of military and his police are also part of the group or at least helping them. If another country steps in to help, the group can be defeated.