[Feliandreka]

Ok, so the Eagles protected Gondolin for hundreds of year and the secret of its location was only betrayed at the end by Hurin and Maglin, persons out of the control of the Eagles.

Does anyone think that Manwe, to whom the Eagles serve, was their air traffic controller, governing their flight patterns and telling them what to do at every turn? No. Absolutely not. The Eagles were very intelligent. The descendants of the same birds who protected Gondolin lived in the Misty mountains in the time of the war of the ring. Can we not suppose they were just as intelligent, though perhaps diminished in stature from the birds of old, and had their own means to follow the events of the world? Who can suppose they were not aware of the Battle of Five armies? All they had to do was look down. They hate goblins as much as men and elves and dwarves. What better time to kill them when they are in the open attacking their own humanoid allies?

The point is, nobody had to tell the Eagles what to do. This idea that Manwe was still ordering them about in the 3rd age does not seem realistic to me. The Eagles governed their own affairs and had their own sources of information. Helping Gandalf was on their adgenda, as was aiding the Heir of Numenor. It is in their very nature, so long as they retain some measure of their former stature, be it size and or inteligence, to oppose Sauron and his minions.

Who can say what Tolkien thought on matters such as this. He probably thought less about it that all of us do. But his writings are poetry and his world like a religion. The faithful have no choice but to speculate. It is really fun!