It would seem obvious that since he plotted, incited and acted upon wanton destruction and murder of innocent people, he was evil personified and it was a mitzvah to eliminate him. Therefore, the successful commando raid that killed him, and collected anti-terror intelligence, is certainly a cause for celebration.
However, we find sources in Jewish texts that seem to be teaching us not to celebrate another’s death. King Solomon states in the Book of Proverbs “Do not rejoice at the downfall of your enemy, and his demise should not cause your heart to celebrate (24:17).
Another source that seems to teach us to refrain from celebrating our enemy’s death is found regarding the Exodus from Egypt. The Israelites successfully crossed the Red Sea, whereas the pursuing Egyptians were drowned and destroyed. Our Sages state that God disapproved of the subsequent celebration and said, “How can you sing when my people are dying?” (Babylonian Talmud, Sanhedrin 39b).
Nevertheless, these sources present no contradiction to our current celebration. The verse in Proverbs and the Talmudic statement are teaching that we should not celebrate the downfall and death of any human being who was a product of the Creator. Our Creator created him as well as us, but unfortunately he chose to be evil to the point of forfeiting his right to exist. When kept in this perspective it is certainly correct to celebrate, but without forgetting that mankind was created in the image of God.