They are real good fighters. Not terrific conversationalists, and their table manners can make you go blind in one eye, but really tough behind the weapons consoles. If there are any other unneutralized Non-Aligned fleets participating in the conflict on the same side, this fleet cannot be attacked. It takes something as big as a full scale war with the Shadows to pull the various species of the galaxy together into a single fleet. For each 2 Non-Aligned species in your Inner Circle, reduce your cost to sponsor this fleet by 1.
Help can come from unexpected quarters, but there is always a price to pay.
And you will never know the price until after the conflict is over. This fleet may attack any Non-Aligned fleet controlled by another player. Other Non-Aligned fleets may attack this fleet in return. One problem with the League worlds is, without a firmer alliance of some sort, a member may attack anyone, within the League or outside it. A security fleet is a step towards consolidation.