Tenet notes a paper produced by the CIA that warns of negative consequences of an invasion of Iraq. But he stipulates (page 318):
It’s tempting to cite this information and say, “See, we predicted many of the difficulties that later ensued”—but doing so would be disingenuous. The truth is often more complex than convenient. Had we felt strongly that these were likely outcomes, we should have shouted our conclusions. There was, in fact, no screaming, no table-pounded. Instead, we said these were worst case. We also, quite accurately, labeled them scenarios. We had no way of knowing then how the situation on the ground in Iraq would evolve. Nor were we privy to some of the future actions of the United States that would help make many of these worst-case scenarios almost inevitable.