"The prospect facing the people of Iraq should serve as sufficient warning that in future we too might have others descend on us, guns in hand to force-feed us (with democracy)," he said in Pretoria.
"If the UN does not matter... why should we, the little countries of Africa that make up the African Union, think that we matter and will not be punished if we get out of line?"
Mbeki was opening a conference on elections, democracy and governance in Africa.
He made his remarks on Iraq after imploring delegates to take an honest look at how democracy was functioning on the continent.
Mbeki said those making war on Iraq contended that they had taken up arms to transform that country into a democracy. The proposition was that democracy could be imposed - "in much the same way that one can force-feed a person on a hunger strike".
"Presumably the argument is that whether a person ingests jollof rice voluntarily or does so because he or she is force-fed, the fact remains that they have eaten jollof rice."
Mbeki added: "I am not certain that the institution of a democratic system can be approached in the same way that we approach the consumption of jollof rice."
He said the central question that needed to be answered was how the rule book of democracy should be applied in Africa.