India is woefully unprepared for any enemy activity on the East Coast. And the deep south is not far from the shipping lines in the Indian Ocean, and there will be increased infiltration by both Chinese naval vessels and submarines. As is rather clear, the Indian Ocean (through which 80 percent of oil shipments pass already between the straits of Hormuz and Malacca) will increasingly become a focus of both trade and warfare.
India needs to be prepared for both. On the one hand, Thoothukkudi port has been refurbished and upgraded, and it should enjoy increased traffic as the national highways from Bangalore and Chennai have become functional. However, it suffers from its location, which requires a bit of a detour, discouraging larger vessels from docking there. But it could be perfect for smaller feeder craft.