Is it going to change anything? Probably not. At the end of the day everyone is complicit is some respect. Part of those taxes taken out of your paycheck are consequently going to defense and the military. The US spends 35% of the world's share of military expenditures[0]. Project Maven was going to happen with or without Google's help, it's just a matter of when. Who knows, they might even be using TensorFlow.
At the end of the day, there's little "defining" for Google to do. Google is not some angel child that fell into dating a bad boy with the DoD. Google does both good and bad things all the time, even when the consequences are not as highly publicized as with Project Maven. Google is a for-profit company that was following the money. Figureheads like Eric Schmidt dove right in to working with the DoD without even giving it a second thought, and there was little news from any C-levels on the matter prior to this PR issue for Google, which I think speaks for itself about the philosophy of the company from its leadership. Cynically put, Google now cares because their reputation, and by proxy their fiscal performance for their shareholders, is now threatened and somebody calculated that the risk is greater than the reward of the government contract.
[0] https://en.wikipedia.org/wiki/List_of_countries_by_military_...