"Peace" is not the absence of violence.Personally I would have prefered that all this time and effort is spent on something peaceful and not a high tech killing machine.
This is one of the "tools" that helps to contain the violence in this world by destroying the tools of violence used by violent people. And yes, collateral damage is expected.
We do not like the idea of safety by total isolation so we allow the potential man operated flights that knock down tall buildings in our country. Because of this there may be times that we feel it necessary to eliminate certain elements who may have the idea to try knocking down more of our tall buildings. It is our responsibility to do this with minimal risk to the lives of our and your good citizens.