New Delhi, Oct. 2 -- Tunnel boring machines (TBMs) have quietly become a critical chokepoint for India. Every metro line, hydropower tunnel, urban water system and cross-country rail project depends on them, yet we import TBMs from a handful of foreign suppliers. Our market, worth Rs.8,000 crore in 2023-24, is projected to cross Rs.11,000 crore by 2029-30.

As we make no large diameter TBMs (10m and above), we remain vulnerable to a Chinese supply squeeze. Recently, China not only halted direct TBM exports to India, but also reportedly blocked subcomponents made in Chinese facilities of a German firm, choking supplies at two levels of the chain.

As a geopolitical lever, TBM holdbacks could delay or derail India's infrastructure plans. Th...