WASHINGTON - The Pentagon will adopt a new strategy that for the first time orders the military to anticipate that future conflicts will include a complex mix of conventional, set-piece battles and campaigns against shadowy insurgents and terrorists, according to senior officials.
The shift is intended to assure that the military is prepared to deal with a spectrum of possible threats, including computer network attacks, attempts to blind satellite positioning systems, strikes by precision missiles and roadside bombs, and propaganda campaigns waged on television and the Internet. The new strategy has broad implications for training, troop deployment, weapons procurement and other aspects of military planning.
In officially embracing hybrid warfare, the Pentagon would be replacing a second pillar of long-term planning. Senior officials disclosed in March that the review was likely to reject a historic premise of American strategy - that the nation need only to prepare to fight two major wars at a time.
Driving both sets of developments are lessons learned from the past six years, when the United States has been fighting two wars in Iraq and Afghanistan, yet is stretched to be ready for potentially significant operations elsewhere, Pentagon officials say, such as against Iran, North Korea or even China and Russia. Conflicts with any of those countries would also be expected to present a hybrid range of challenges.
But powerful constituencies in the military and in Congress continue to argue that the next war will not look like Iraq or Afghanistan, and they say the military is focusing too much on counter-insurgency and losing its ability to defeat a traditional nation-state.
Even so, senior officials say hybrid warfare will be adopted as a central premise of military planning in the top-to-bottom review required every four years by Congress. When completed later this year, the assessment, officially called the Quadrennial Defense Review, will determine how billions of dollars are spent on weapons and influence how the military reshapes its training.
During a Pentagon news conference last week, Defense Secretary Robert M. Gates said of the new strategy, "It derives from my view that the old way of looking at irregular warfare as being one kind of conflict and conventional warfare as a discreet kind of warfare is an outdated concept. Conflict in the future will slide up and down a scale, both in scope or scale and in lethality."
Even before the review is complete, the new thinking has claimed high-dollar victims.
Mr. Gates proposed ending production of the Air Force's top-of-the-line F-22 fighter jets, arguing that money should be spent on warplanes that carry out a broader array of missions, from countering enemy air forces to evading surface-to-air missiles to bombing insurgent militias in hiding.
But supporters of the F-22 in Congress are pushing for financing to keep the production line open, potentially setting up a veto battle.
The defense secretary also put on hold a multibillion-dollar program for the Army's next-generation armored vehicle, saying its proposed flat-bottom design ignored lessons that angular troop transports are safer from roadside bombs, which have been the biggest killer of troops in Iraq.
In preparing to adopt concepts of hybrid warfare, the Defense Department has closely studied Israel's last war in Lebanon in 2006, when a terrorist group, Hezbollah, fielded high-tech weapons equal to any nation's, including long-range missiles. Likewise, when a traditional military power like Russia went to war with the former Soviet republic of Georgia last August, its tanks, paratroopers and warships were preceded by crippling computer network attacks.
The previous Pentagon strategy review focused on a four-square chart that described security challenges to the nation as perceived then. It included traditional, conventional conflicts; irregular warfare, such as terrorism and insurgencies; catastrophic challenges from unconventional weapons used by terrorists or rogue states; and disruptive threats, in which new technologies could counter American advantages.
"The ‘quad chart' was useful in its time," said Michele A. Flournoy, the under secretary of defense for policy, who is leading the strategy review for Mr. Gates.
"But we aren't using it as a point of reference or departure," she said in an interview. "I think hybrid will be the defining character. The traditional, neat categories - those are types that really don't match reality any more."
The nation's top military officers are reviewing their procurement programs and personnel policies to adapt to the new environment, focusing in particular on weapons systems that can perform multiple missions.
"When I send a carrier strike group forward, or when I send an amphibious ready group forward with a Marine Expeditionary Unit on board, I don't know what they are going to end up doing," said Adm. Gary Roughead, the chief of naval operations. "Therefore, the way that we view our training, the way that we view our capabilities, has to be packaged for this range of actions."
He cited the experience of the aircraft carrier Abraham Lincoln, which was steaming toward Iraq to carry out combat missions when it was diverted to become the American headquarters for tsunami relief in Indonesia. Both Admiral Roughead and Gen. Norton A. Schwartz, the Air Force chief of staff, said in interviews that they had adopted goals of making certain each weapon system could "stretch" across a spectrum of operations, proving value in traditional and irregular warfare.
General Schwartz cited Air Force decisions to place surveillance systems on its long-range bombers and tactical warplanes to make each a provider of valuable battlefield intelligence, as well as maintaining strike capabilities.
"This is the kind of thing we are talking about, where we avoid point-mission platforms and look for versatility," General Schwartz said. "Multipurpose platforms are inherently more affordable."
For the ground forces, the goal is an ability to sustain 10 combat brigades abroad at all times, with 10 more in reserve and nearly ready to go as they complete training. This eventually would allow active duty troops to spend three years at home for every year deployed.
Gen. George W. Casey Jr., the Army chief of staff, when asked to define the Army's goals in the review, said: "The most significant thing I'd like to get is an acceptance of that rotational model.