There is a massive difference to us compared to what they do , We bomb training camps to try stop terrorist acts like what has just happened in France and sadly civilians will get killed , that does not give these Terrorist the right to come too our country and mass murder innocent people in the streets , The US / France / Britain Germany ect don't drop bombs to murder innocent people, we do it simply to stop terrorist from planning future attacks.
The sad thing with all this is the more terrorist acts we see like this happening the more the peaceful nations will unite together to wipe this evil from the planet, This morning I woke up feeling like this and I'm pretty sure most of the world did too , Sad , heartbroken , angry , revenge , why ? - its a massive cycle and seeing what has happened is only going to fuel more bombing campaigns.