I don't know, that's an interesting question. I believe the question is really about semantics though. It's like an escher drawing.
It is self evident that doing something God loves is piety. The question is whether anything can be piety that God does not already love. There are prescribed acts that God loves.
Worship as He has directed us in Holy Books that He revealed to us through prophets and messengers. It is definitely piety to do those things. But there are other acts that God loves that He did not already tell us to do, and humans in day to day life are always confronted with opportunities to do good that do not fit in neatly to what He already taught us, and I would say that the really powerful way to access God's love is through those acts that He didn't already tell you to do beforehand--those acts are the ones that show deep faith inside the person, or that show a depth of some other good quality, like love or restraint or generosity.
Interesting question thank you. One thing--it's impossible to do something that God did not previously know about--He created you and also your (and my) behavior before we came into this world. Anyway I don't really know if this question is really more wordplay than legitimate question but I sense something real in it and I tried to answer although I'm not sure I did it well.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.