What do you need to receive a Nobel Peace prize?

Oslo has announced that Nobel Peace prize has been given to Martti Ahtisaari, former president of Finland and UN envoy.

Why Mr. Ahtisaari? According to the Nobel Committee, he was commended "for his important efforts on several continents and over more than three decades to resolve international conflicts". He has been the United Nations special envoy for talks on the final status of Kosovo and mediated a 2005 accord in Indonesia's Aceh province.

Why? He has been a "peace negotiator".

Then, why peace making efforts (by force) do not deserve Nobel Peace prizes?

The picture is "Daniel in the Lion's Den" painted in 1600 by Sir Peter Paul Rubens, the man who painted the Monasterio del Escorial and was so expresive in human flesh.