Ahtisaari added that while Osama's death might make the world slightly different than before, al-Qaida operations had been led from a place other than his hiding place even while he was still alive.
Ahtisaari said that the real work to root out terrorism involved poverty and youth unemployment mitigation.
"These issues can be managed," Ahtisaari said.
"I am angered by the fact that international cooperation is so amateurish. It is such amateurish tinkering that one is simply appalled by it."
"People would lose sleep if they only knew."
Ahtisaari expects al-Qaida to begin a campaign of reprisal attacks in Pakistan.
Ahtisaari's response to the reported killing of Osama by US special forces in Pakistan stands in contrast to comments by Alexander Stubb (cons), the Finnish foreign minister.
Stubb had hailed the killing of Osama as a historic milestone in the fight against terrorism and said Monday that the world was now a safer place than it was when the terrorist leader was alive.