Threats to national security reach far beyond what has traditionally been viewed as the risk of state-on-state conflict. The US National Security Strategy focuses on the threats of global terrorism, regional conflicts, and the proliferation of weapons of mass destruction, but fails to address the root causes of these threats and therefore lacks the foresight to mitigate substantive risks before they manifest as destructive forces. Environmental degradation and resource shortfalls, most notably access to fresh water, brought on by a burgeoning global population threaten to foster social unrest, destabilize regions, and negatively impact international commerce. The global fresh water crisis is a threat to US national security -- a threat the United States can address proactively.