In September 2016, standing before a rally in Kerala, Narendra Modi made a promise. India, he declared, would launch an all-out campaign to isolate Pakistan. It was the kind of thinking that plays well in a crowd - muscular, self-righteous, vengeful. A decade on, Pakistan is simultaneously engaged with Washington, Beijing, Tehran and Riyadh; has brokered a ceasefire between Iran and the United States; and has been credited by Donald Trump for sa…