Enemy A.I. won't die

[lithiumxsl]

I've been playing the game using alot of intel tactics, stealing ships, plaguing, sabatoge, along with all out mayhem against the enemy A.I. In particular, I've been annoying the Kithra. But now that I have them where I want, I can't kill them. I point to attack but nothing. I have no treaties and I pronounced myself at war with them. What gives? The only thing I can do is have them surrender. Oh joy! Oh how I love rioting planets. Anyway, is this a glitch? I literally can't attack anything of theirs. My weapons and armor are 3 x's better than theirs. Please help.

Lith