Following the 2008 Mumbai Attacks, India refrained from engaging in counterterrorism cooperation with Pakistan, the origin country of Lashkar e-Taiba (LeT), marking a significant departure from previous approaches. This study investigates the factors influencing India's decision through the lens of the Prisoner's Dilemma Theory. By examining India's strategic calculations and contextualizing them within the security dilemma framework post-Mumbai terror, this research aims to elucidate the rationale behind India's non-cooperative stance. Results reveal a complex interplay of historical distrust, perceived security threats, and strategic considerations shaping India's decision-making, highlighting the implications for future counter-terrorism efforts and international relations strategies.