It would not cost much; they pay only for a telegram, and the upstart civilization obediently destroys itself.
In the long run, the aggressive civilizations destroy themselves, almost always.
Roughly one thousand solar years ago, the civilization destroyed itself.
A whole civilization destroyed by greedy, righteous bigots.
But sure as I'm standing here with you civilization would have destroyed me.
There was nothing but ruins, a civilization destroyed, a race exterminated.
Of the millions dead, and the civilizations destroyed.
He believes that advanced civilizations destroy themselves.
Ultimately, the Empire lost interest and decided that such a violent civilization must have destroyed itself somehow.
Usually the civilizations had been pre-warp and had destroyed themselves.