I was actually thinking about Israel and how they could possibly be involved in the WMD issue. This is just a theory, and, no, I don't own a tin foil hat.
Israel has had a good reason to stay out of the US Iraq invasion. Adding a few more logs to the Zionist-hating Islamic radicals is not a wise choice, especially in the current Roadmap for Middle East Peace. While Israel certainly had a ton to gain by Saddam's removal, as evidenced by the Perle document link you posted, they really had even more to lose by helping to do it.....at least openly.
The US intelligence infrastructure has been moving away from HUMINT (human intelligence) and depending more on sensor based data collection over the years. As technology has improved, so has the absolute requirement for "double O" type agents. I am sure the CIA still has many but I am willing to bet the number has been dwindling.
If you were loking for an ally to help you collect HUMINT in the Middle East, who would the US probably look to first? That's right, Israel. I think it is definitely plausible that Israel assisted the US intelligence effort, actually the world intelligence effort to help provide the basis of the evidence for Saddam's WMD efforts.
Since the Israel-US connection in relation to any assistance for the regime change in Iraq must remain absolutely secret, even after Saddam is captued, wouldn't this give Israel the opportunity to exagerate WMD intel to the US and UK with no accountability?
Wouldn't this explain the complete breakdown of US/UK intelligence? This is easily a common source of intelligence for the US and UK. Could Israel have intentionally betrayed us to further their plans for a Middle East that is safer for them?
This theory, if true, would certainly go a long way to exonerating the CIA, NSA and the Bush administration. The only problem is, if exposed, it would really make things much more unstable in an already teetering Middle East.