WASHINGTON: Prime Minister Narendra Modi is likely to use the military option if the next terrorist attack in India is traced back to Pakistan, a former top US diplomat has warned while hoping that the Pakistanis would understand that their past behaviour is unlikely to be tolerated now."Every Indian Prime Minister since the attack on the Parliament in Delhi now heading on 15 years ago has looked seriously at a military response when these incidents occur and has stepped back. But I believe that sentiment inside India has changed substantially and I think this Prime Minister is unlikely to step back," former US Ambassador to India Robert Blackwill said."If there is a major terrorist attack whose breadcrumbs lead to Pakistan and the Pakistan military and ISI, I think that this Prime Minister is likely to use military force against Pakistan territory. It's not a certainty," Blackwill told reporters during a conference call organised by the Council on Foreign Relations (CFR), a top American think-tank.Blackwill, who is a close watcher of India and South Asia , said Modi's predecessors have been briefed by the Indian military on options and have never found them attractive."But I think Modi, both as a personality and reflecting Indian public opinion and political sentiment across the society will be much more likely to use military force than his predecessors," he said."Now how that might be applied is another matter. To try to diminish the likelihood of escalation between two nuclear weapon states, but hopefully the Pakistanis understand that their behaviour in the past is unlikely to be tolerable to this Indian Prime Minister," Blackwill said in response to a question.Stephen Cohen, senior fellow in foreign policy at the Brookings Institute, agreed that Prime Minister Modi's response to a terrorist attack emanating from Pakistan would be a different one than that of his predecessor."I think based on what he (Modi) said and I think based on the Indian public sentiment, if there was another Mumbai attack, which I don't think it's going to be that likely, it (India's response) may be something quite different. There will be a vigorous Indian response. Perhaps even direct attacks on Pakistani territory, hitting camps," Cohen said.