Rethinking the role of nuclear weapons

In the new era, the United States need not rely on nuclear weapons to prevent a global challenger from upsetting the status quo, to compensate for weakness in conventional defense, or to impress others with its power. Although the threat of nuclear response to conventional attack is no longer crucial to U.S. strategy, rogue states might adopt this tactic to deter U.S. power projection. However, the United States needs nuclear weapons to deter nuclear and biological attack, which could be just as deadly and might not be deterred by threat of U.S. conventional retaliation. The United States could reduce the importance and attractiveness of nuclear weapons, delegitimize their use in response to conventional threats, sharpen nuclear deterrence against biological weapons by stating nuclear weapons would be used only in retaliation for attacks with weapons of mass destruction (WMD)--in essence, a "no-first-use-of-WMD" policy.