Michele Flournoy, a former Pentagon proliferation expert now at the Center for Strategic and International Studies, said that to be effective, the United States will need to strike preemptively before a crisis erupts to destroy an adversary's weapons stockpile. Otherwise, she said, the adversary could erect defenses to protect those weapons, or simply disperse them.
But Flournoy said she favors moving toward a doctrine of preemption given the proliferation of chemical, biological and nuclear weapons among states supporting terrorists. She said the policy may offer the best of a series of bad choices.
"In some cases, preemptive strikes against an adversary's [weapons of mass destruction] capabilities may be the best or only option we have to avert a catastrophic attack against the United States," she said.
Under the doctrine, nuclear first strikes would be considered weapons of last resort, especially against biological weapons that can be best destroyed by sustained exposure to the high heat of a nuclear blast, Pentagon officials said. But the focus of the effort is finding new ways of using conventional weapons to detect and destroy weapons arsenals, and especially the missiles used to deliver them.
To do that, the Pentagon is studying how to launch "no warning" raids that go far beyond quick airstrikes. The key tool to execute that mission is a new "Joint Stealth Task Force" that pulls in the least detectable elements of every part of the armed forces, including radar-evading aircraft, Special Operations troops and ballistic submarines being converted to carry those troops and to launch cruise missiles.
Beyond changes in weapons, doctrine and organization, Rumsfeld and his top aides are trying to alter the U.S. military mind-set. "Preemption . . . runs completely against U.S. political and strategic culture," defense expert Frank Hoffman said in an essay published this year by the Center for Defense Information.
In the past, the United States has viewed surprise or "sneak" attacks as dishonorable, the kind of thing inflicted on the American people, not initiated by them, analysts have noted.
One senior defense official responded that 21st century security threats can no longer be assessed in terms of the past. "In the world in which we live, it's not enough to deter," the official said. "You need more capability, more flexibility, more nuanced options and choices."
Defense scientists and war planners are hard at work developing new weapons and capabilities to give Bush "options different than those he may have had in the past," the official said.
At the Defense Threat Reduction Agency, a $1.1 billion defense agency created in 1998 to counter the threat of weapons of mass destruction, scientists are studying how to attack and destroy hardened and deeply buried bunkers containing chemical, biological and radiological weapons with advanced conventional bombs, low-yield nuclear devices and even high-yield nuclear weapons.
"There was a time during which we really didn't know what phase we were in, so we called it the 'post-Cold War phase,' " said Stephen M. Younger, the agency's director. "And it wasn't clear what kind of weapons we were going to need for the conflicts of the future. September 11 clarified that. And we are getting a better understanding of the types [of threat] we may face in the future and the types of weaponry that will be required [to counter] them."
Younger said his agency is working on advanced conventional explosives with hardened warheads that could penetrate underground concrete bunkers and destroy biological agents with a sustained level of extremely high heat.
"We want to use the minimum force to achieve the military objective, if at all possible, with a conventional weapon," Younger said. "We do not want to cross the nuclear threshold unless it is an example of extreme national emergency."
But there are some bunkers that are "so incredibly hard," Younger said, "that they do require high-yield nuclear weapons." Low-yield nuclear warheads could be useful in certain scenarios, he said, but they run the risk of spreading biological agents across the countryside.
Rumsfeld's Nuclear Posture Review, completed at the end of last year, stated that "new capabilities must be developed to defeat emerging threats such as hard and deeply buried targets." It also said "several nuclear weapons options" that could be useful in attacking such facilities include "improved earth penetrating weapons."
But senior administration officials said the tactical use of nuclear weapons is being studied, not actively contemplated. "There is no one anxious to think about the employment of tactical nuclear weapons," a senior defense official said. "That's not what we are trying to do."
What the Pentagon is most focused on, the official said, is a method of "advanced conventional strike."
Inside the Pentagon, some officials suspect that the new doctrine may be acted upon sooner rather than later.
"I think the president is trying to get the American people ready for some kind of preemptive move" against Iraq, said a Pentagon consultant. He said it would not necessarily be against Iraqi weapons sites but might instead involve a seizure of Iraqi oil fields.
But a senior administration official dismissed the idea of a "bolt from the blue" attack on Iraq. "I want to caution that [the president] was not making an announcement about imminent action" in his West Point address, the official said. "Some people have quite frankly said, 'Oh, this must have been about Iraq.' He was not making an announcement about imminent action, but this was a doctrinal statement."
Rumsfeld may have captured this situation best when he declined to discuss preemption last week. Asked in an interview whether the U.S. government is contemplating preemptive moves against other nations' weapons of mass destruction, he replied: "Why would anyone answer that question if they were contemplating it?"