Former Indian foreign secretary Ranjan Mathai (66) has been keenly following the dramatic developments in India’s neighbourhood in recent months. A 1974-batch officer of the IFS, Mathai had been instrumental in formulating many policies when he was handling Bangladesh, Myanmar, Maldives and Sri Lanka as Joint Secretary BSM in South Block. He talks to Pranay Sharma on China’s growing footprint in South Asia and how effective PM Narendra Modi’s policy has been in meeting the challenges India faces in its backyard. Excerpts: