I think its no big deal that ISI did not know where osama was. I do not think the argument that if they knew they were complicit and if they didnt they were incompetent is acceptable. This argument has been postulated by the enemies of pakistan, America India etc. The reason that this has been forward is because ISI and Pak army will only cooperate with america to a certain degree they will not give carte blanche to do whatever they want. For example America would like ISI and Pak army to not be freindly to china. But Pakistan army and isi will not listen to them.
This is a clever argument because its easy to get drawn into and then when we do ISI is damned if the knew and damned if they didnt.
I would say that in a country of 180 Million with the land mass that is pakistan if an individual with a brain and some money its not that difficult to evade the state. I mean if you look at the FBI most wanted list there are lots of people who eveade capture after murder etc for decades its not such a big deal. Same with Indias most wanted or any country in the world
Long Live Pakistan its army and ISI the defenders of our nation