Celebrating the death of anyone, regardless of their behaviour, is disturbing to me. It just brings you down to their level. Trying to fight hatred with hatred is futile. A fact proved repeatedly by humanity over the past 4000 years (or more). The only way to fight hatred is with love. You may not win specific battles, but you will win the war as love is thousands of times more powerful than hatred.
Its easy to love you friends and family. Its much more difficult to love your enemy, but we have been told to do this by successive religions and it has been demonstrated repeatedly to work.
The false notion is that if I am passive and show love to my enemy, and he responds by killing me - then my enemy has won and I have lost. This make perfect sense to the atheist, but to a genuine theist, no, my enemy has lost and I have won.
What is more important to me than my life is how I live it.
And to those of you who challenge this ideology - don't expect to see any changes in the world you are complaining about.
Peace.