When I said that, "There has always been a faction of the aliens who are not satisfied with just being observers," I was thinking about what is called the "interventionists". All of the aliens in Earth's Fence Area are supposed to be here as Observers, but there are factions of Observers. One of the hardest things to explain to someone from a different culture are the political factions of another culture. The problem in explaining Observer factions is that there is almost no difference between them, yet the tiny differences that do exist are the basis for endless (well, it only seems endless; these struggles have "only" gone on for about a billion years) conflict. At the risk of greatly trivializing and over-simplifying, I'll say that the Interventionists are those who hold weak interpretations of the Rules of Alien Contact. The interventionists think it is criminal to sit and watch as a species like yours (Earth humans) struggles along. "What's wrong with a few helpful nudges?" they ask. Of course, the only thing wrong with it is that it is against the law and a whole army of fanatically strict Observers is swarming around Earth just waiting to slap the hand of any Interventionist who tries to intervene in the development of life on Earth.