Transcendence

In other words, I destroyed a Dwarg base from a distance with an omni particle weapon without hurting any of the Dwarg guards and something strange happened... nothing. The Dwarg ships continued to circle around the destroyed base until I came in to loot it. None of them became followers and none of them retaliated (until I got too close of course). And no, there was no Dwarg capship there either so that wasn't it.
On a related note, it's funny when a Commonwealth fortress or something like that destroys a wandering Dwarg capship and the capship's escorts become followers of the base.