Politics

Sentences like "I think this is exactly the right position - as a legal matter, as a policy matter, and as a political matter" (Elena Kagan) tend to puzzle me. What is the difference between a policy matter and a political matter?
Both words derive from Greek polis, meaning city, state. However, while a policy is "a way of doing something that has been officially agreed on and chosen by a political party," or "a particular principle one believes in and influences the person's decision making," political means anything "relating to the government, politics, and public affairs." Thus, a policy matter is a party matter while a political matter is anything that affects government and the public.
An other difference between a policy and a political matter becomes apparent when the second meaning of political is applied, namely "relating to the ways that different people have power within a group." It is the huge difference between a guiding principle that members of a party share and their way to gain, sustain and use power. Interestingly - but not surprisingly - enough, political has a pejorative connotation, implying that being political means "taking sides in party politics" (Online Etymological Dictionary). In other words, it is a euphemism for partisan and has little to do with a guiding principle but a lot with power.