Pakistan's agency were involved in 26/11, there is no doubt about that. Turning blind eye to the fact doesn't change the truth. ISI and Co were involved and guiding the attackers till their death is well proved by not one (RAW) but other agencies like FBI and Scotland Yard. This is what the world believes any way. It is not only India the World blames Pakistan for international terrorism. Read what FBI came out with after interrogating Hadley;
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The very fact that Hillary Clinton repeatedly states that elements in Pakistan's govt know where Osama is, explains what sort of governance we are having in Pakistan. There are evidences that ISI was involved in attack on Indian Embassay in Kabul. This has been established by FBI. The details of war logs unleashed recently sends chills down the spine about Pakistan and intentions.
WAR LOGS-Telegraph UK
Pakistan appears to be a country constantly at war with India. Going by what India has suffered in last several years after operation K2 launched by Pakistan this surprising and interesting that a section in India still believes peaceful coexistence is possible with Pakistan. Hope I would be proved wrong but deep inside I know this is false.
Now to the final part; cultural exchange is possible when at least two govt are not at war with each other. Failed secretary level talks and on going war of words prove who pulls strings in Pakistan.
Yes the kids are talented and not at fault but when relations are estranged we can't sing and dance (something similar to collateral damage).