"The second thing is more mundane but nevertheless true -- the higher you go up the policy food chain, the less detail in the memos. The reason is that the most precious commodity of cabinet-level officials is time. They're scheduled to within an inch of their lives -- the last thing they have time for is 'assessing the veracity of the underlying raw intelligence.'I agree with the perspective, but would amplify. The intelligence community has often been viewed as in-bred and biased, a "stovepipe" (or set of stovepipes) in itself. There's a long history of attempts to bring a different perspective to security issues (the Gaither Commission in 1950's which came up with the "missile gap"; the Team B effort in the 70's). Cheney and Rumsfeld had Feith do a shop in DOD that ended up pushing the al-Qaeda/Hussein link.
This is why stovepiping is so dangerous. [The allegation is that the presentation bypassed normal staffing and went up the stovepipe to the President.] Even with a decision as momentous as going to war, a president is rarely going to devote the time to assessing the accuracy rate of intelligence briefings. More likely, they'll assume that if it gets to their desk there must be something there there.
I'm not saying that there wasn't a willful blindness in parts of the White House about this intelligence. But never underestimate the cognitive limitations of policy principals that time crunches create."
In a broader sense, any executive needs to avoid becoming the captive of her bureaucracy, relying only on the information coming up the stovepipes. FDR was famously disorganized, setting up competing agencies, talking to everyone, with the result that he wasn't captive of any bureaucracy.
But today shows the flip side of the coin. If you go outside the stovepipe and are wrong, as the Iraq intelligence was, the bureaucrats in the stovepipe get very, very pissed off. Or, using a positive spin, they believe that leaders who have proven their incompetence should not have a monopoly on the information presented to the public. Hence the leaks.