Hate breeds hate, only causing pain to the one generating it.
The victims are long dead, they do not suffer. The families of the victims need to deal with their loss, but hate has probably long left them as they realise that it will not bring back their loved ones.
It is poignant to think of the victims and how they were enjoying life when they were snatched so early. This is the memory which should be held and lived as they so did.
Do not waste your energy thinking of the perpetrators as it is the designed intention of their actions.
Also do not be fooled by their smiles, as it too is designed to magnify their actions.
The only weapon that will defend the terrorists is to weaken their base by leading an example contrary to their beliefs. That is, right mind, right thoughts, right actions.
