1971 was a different situation that doesn't exist anymore, and 1971 was probably avoidable if there was no 1965.
NOW we do not gain anything or fulfill any objective by starting a full scale war with Pakistan, unlike in 1971.
But, in case of another 26/11 like terrorist attack on us, we will likely to respond with a limited strike on Pakistani terror camps across the border areas with India, because it will serve multiple purposes for us, most important of it is to raise the stake for the international community to continue to maintain a relatively tolerant attitude to countries harbouring terrorists, and compel the international community to force Pakistan to destroy its terrorist assets and accept a border solution as per our preference.
Pakistan may respond disproportionately to our limited strike up to a point, and it will be responded to suitably, but after that it is expected that better sense will prevail among Pakistani leadership, and they will stand down. And if they don't, then I would say you missed the very last part of my previous post that says "or bigger powers won't". You might want to believe otherwise, but USA has significant control over Pakistan, they won't want the war to stretch beyond a point. Besides, China has increasing amount of investments in both India and Pakistan, they won't want that to go waste, and China also has significant say over Pakistan, they will make sure that Pakistani leadership act as per their best interest.