Citing Carl in part:
...how we got so thoroughly fooled by the Pak Army/ISI.
Prompted me to recall an exchange with a retired USG decision-maker, who was closely involved in monitoring Pakistan's nuclear developments and in particular the leading scientist, Dr. Abdul Qadeer Khan, known as the ' the father of Pakistan's nuclear programme'. See:http://en.wikipedia.org/wiki/Abdul_Qadeer_Khan

Several times Dr. Khan was outside Pakistan on his missions, with "hands on" access to incriminating evidence and each time those further up the command chain declined to authorise action.

The USG decision-maker IIRC referred to an overwhelming US national interest in the maintenance of at least a friendly Pakistani state, that was not totally opposed to the interests of the USA and allies.

This seems a rather high price to pay given what happened over the conflict in Afghanistan, but as I have posted before Pakistan is far more important than Afghanistan.

Yes an element of being 'fooled' existed, I suspect more of the explanation and blame rests closer to home than the murky corridors of the Pakistani Army/ISI.