Apr 6, 2010 3:41 PM by Bea Karnes, News First 5
The Obama administration is pledging to reduce the role of nuclear weapons in the nation's defense.
The administration's nuclear posture review, released Tuesday, asserts with caveats that the United States would not use nuclear weapons to respond to a chemical or biological attack.
That assurance would only apply to countries that had signed the Nuclear Non-Proliferation Treaty and met its obligations.
Because such countries pose a threat, the administration said it could not declare deterring a nuclear attack the "sole purpose of nuclear weapons."
But the administration added it would work to establish conditions under which such a policy could be safely adopted.
The U.S. said it might change the policy if biological weapon technology developed more catastrophic potential.