The phenomenon of Internet fragmentation is an increasingly pressing issue, driven by geopolitical, economic, and regulatory factors, as well as the growing sophistication of cyber threats. Malicious actors are leveraging emerging technologies such as artificial intelligence, machine learning, and quantum computing to execute more advanced cyberattacks, posing significant risks to critical information systems and the stability of cyberspace. These evolving threats directly impact key Internet infrastructures, including addressing, naming, and routing (ANR), accelerating the process of Internet fragmentation. This paper examines Internet fragmentation through a multi-faceted cybersecurity lens, exploring how cyberattacks disrupt the integrity of the global digital ecosystem. We present a game-theoretic model to analyze strategic interactions between cyber adversaries and defenders, identifying optimal defense mechanisms against Internet fragmentation. Additionally, we introduce a Markov Decision Process (MDP)-based framework to model the probabilistic evolution of fragmentation over time, helping predict the long-term stability of global networks under persistent cyber threats. Furthermore, a graph-based security model is used to assess the structural vulnerabilities of Internet connectivity, quantifying fragmentation through network resilience metrics. Given the increasing complexity of cyber threats, governments and organizations must enhance their cyber resilience to mitigate fragmentation risks and preserve the unity of cyberspace. This paper addresses key research questions on the correlation between cyber threats and Internet fragmentation across its three categories, technical, state, and commercial. We analyze whether cybersecurity can serve as a unifying framework to counteract fragmentation and propose structured methodologies for mitigating its risks.