Customary international law (CIL) is classically understood to arise from two elements: widespread state practice and *opinio juris*, the belief that such practice is legally obligatory. Applying this traditional framework to state-sponsored cyber operations, however, presents unique evidentiary hurdles. Because cyber operations are frequently conducted in profound secrecy and often routed through proxy actors, definitively identifying state practice in cyberspace is notoriously difficult. States rarely publicize their offensive cyber capabilities, and victims of cyberattacks often hesitate to formally attribute them for fear of escalating hostilities or revealing intelligence-gathering methods.
Consequently, a growing chorus of legal scholars contends that the traditional two-element approach to CIL is inherently unworkable for cyberspace. These critics argue that the international community should instead abandon efforts to apply CIL to cyberspace and rely on "soft law"—non-binding norms and voluntary guidelines—to regulate cyber conflict. They point to the success of recent United Nations working groups in establishing voluntary norms of responsible state behavior in cyberspace as evidence that soft law is a more pragmatic approach.
This conclusion, however, is dangerously premature. While the opaque nature of state cyber operations poses significant evidentiary challenges to identifying state practice, the traditional framework of customary international law remains the only viable mechanism for establishing universally binding restraints on state behavior in cyberspace, and must therefore be adapted rather than discarded. Soft law, by definition, lacks the compulsory nature necessary to deter sophisticated state actors from engaging in destructive cyber warfare.
The adaptation of CIL does not require diluting its rigorous standards, but rather broadening our conception of what constitutes observable state practice. By analyzing official public attributions of cyberattacks, diplomatic responses to cyber incidents, and national cyber defense doctrines, international lawyers can gather sufficient evidence of state practice and *opinio juris*. This broader analytical lens allows the traditional CIL framework to function effectively in the digital domain, ensuring that cyberspace does not remain a lawless frontier.
Which one of the following most accurately expresses the main point of the passage?
- ACustomary international law must be adapted and preserved because it is the only viable mechanism for establishing universally binding restraints on all forms of modern covert and asymmetric warfare.
- BBecause the traditional two-element approach to customary international law is unworkable in cyberspace, the international community should rely instead on non-binding guidelines to regulate cyber conflict.
- CBecause cyber operations are often routed through proxy actors and conducted in profound secrecy, definitively identifying state practice in cyberspace is notoriously difficult.
- Despite the profound difficulties in observing state practice regarding cyber warfare, the established structure of customary international law must be adapted and preserved, as it is the sole means of establishing binding global limits on state cyber operations.Answer
- EThe adaptation of customary international law to cyberspace requires diluting its rigorous standards in order to broaden the legal conception of what constitutes observable state practice.