Con-pilot has posted a question which deserves an answer:
The question that MUST be asked is; what is the worse that would happen if either side were wrong?
I will have a go.
The USA and indeed much of the world faces a terrorist threat from al Qaida. We do not know much about how or where the next blow will come. The little pieces of information that we have are partial and not directly related one to another. Intelligence comes from relating this information, finding possible links and eliminating spurious connections. It is, even if unbiased, highly fallible.
If resources are concentrated on one area of threat to the detriment of others, the risk increases that terrorist preparations in areas less covered will go unnoticed. Political bias (conscious or otherwise) in evaluating intelligence therefore increases these risks.
In acting on limited information about certain flights, is other information being missed?
answer=42