Yes, they absolutely should. Terrorists believe they can get away with anything because there are too many rules in modern day warfare. We should hunt them downand kill them like the animals they are in the most gruesome manner possible. There is no place in the world for killing in the name of any God.
Justice is important in this world. These terrorists who think they can destroy the lives of innocent people need to be found and brought to justice. They should have to suffer the pain that they inflicted on so many others. We owe that much to the victims who lost their lives to these mindless acts of terrorism.
Global terrorism is the largest threat facing the civilized World today. Over the past several years, innocent civilians have been the victims of numerous attacks. The World should do whatever it takes to bring suspected terrorists to justice. Many times, this will mean killing them if they refuse to be captured.
It would be ideal to say that the world should do more to hunt down terrorists but the reality is that terrorists are always going to be hard to find. Civilian casualties are inevitable when the group causing them has a clear disinterest in the people whose lives they take. The people of the world are already doing what they can to capture terrorists with the fewest amount of casualties.