How do nuclear weapons and long-range missiles challenge traditional ideas about national security and sovereignty?

Nuclear weapons and long-range missiles fundamentally challenge traditional concepts of national security and sovereignty by rendering physical borders increasingly porous and difficult to defend. In the era of intercontinental ballistic missiles, the traditional ability of a state to protect its territory from external threats has been severely compromised, as these technologies allow for the delivery of overwhelming violence across vast distances, bypassing conventional military defenses.12

This shift forces states to prioritize deterrence—the threat of reprisal—over the physical blocking of attacks. Because the potential for destruction is so absolute, the focus of national security has moved toward managing the behavior of adversaries and preventing conflict, rather than simply defending frontiers.231

Furthermore, the diffusion of this technology empowers more countries to directly influence the global environment and the security of other nations, creating incentives for international regimes to limit the domestic policy choices of individual states. Consequently, the core of a state’s sovereignty—its ability to independently determine its national security policy—is increasingly constrained by the realities of a globalized, nuclear-armed international system.1