You've got to be careful with this. While submissives can turn on you, you normally must do something to get them to. For example, if Morgan surrenders and I nerve gas everyone to pieces and gain a poor reputation, then he'd probably revolt. Sometimes people say a powerful submissive is also an unruly submissive.
It also depends on what faction. The evil Yang would probably revolt more easily than a more passive country would. Submissives can also rebel if you are framed for a probe team action against them, if you attack them (of course), and if you abuse them by demanding things constantly. That's what I know, anyway
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The fault lies not in our SMAC, but in our stars.
~ Vanguard, February 2, 2000.