India’s nuclear submarine program represents a critical but challenging effort to establish credible sea-based deterrence amid China’s expanding Indo-Pacific naval presence. This comprehensive analysis examines India’s nascent SSBN fleet, currently comprising just two operational submarines with limited-range missiles, against China’s superior undersea capabilities and Pakistan’s evolving nuclear naval ambitions. The report reveals significant gaps in India’s deterrent credibility, from reactor limitations and stealth vulnerabilities to infrastructure delays, while China’s “String of Pearls” strategy increasingly constrains India’s maritime freedom. Despite symbolic milestones like INS Arihant’s patrols, India faces a 50-60-year timeline to achieve truly credible, continuous at-sea deterrence, highlighting the enormous strategic and technological challenges ahead.