Obama Assembles Powerful West Wing

"It's adding a layer of bureaucracy rather than really eliminating one," said Herschensohn, recalling Nixon's failed attempt to eliminate all but four Cabinet agencies. "Everyone will be fighting with everybody. You'll have conflict with every Cabinet officer who will now have a superior in the West Wing or" the adjacent Eisenhower Executive Office Building.

If executed poorly, empowering a small team inside the White House can lead to insular decision making and the alienation of those Cabinet secretaries outside the loop, said historian I.M. Destler, a professor at the University of Maryland's public policy school.

"It tends to lead to disruption, and sometimes chaos, in terms of how the larger government works," Destler said. "It cuts out other people. They think the worst about what's going on in the White House. Loyalty to the president is diminished."

There is also a danger that a weak adviser, or one who is perceived as having lost the backing of the president, will not be able to corral the necessary government resources, becoming ineffective or irrelevant.

"Are all these people really going to have the relationship with the president that they need?" Destler asked. "He seems to be placing a lot of faith in his own ability to manage a team. How much is he going to do it directly?"

G. Calvin Mackenzie, a professor of politics at Colby College, said Obama also risks bogging his White House down with minutiae better left to the Cabinet agencies.

"The dark side of that is that inevitably the White House gets into micromanaging and it minimizes the importance of the Cabinet secretaries," Mackenzie said. "The thing that might make it less than inevitable is that they are starting with this structure in place from the beginning."

Top Obama advisers spent months studying the internal workings of previous administrations and came away convinced that high-priority issues require a White House coordinator akin to the national security adviser. White House veterans say the new posts are the clearest signal yet that the incoming president has no patience for the resistance to change that permeates the capital.

"He's taking his top priorities and doubling down by making sure they are operating in full coordination in the White House as well as in the agencies," said Patrick J. Griffin, who served as President Bill Clinton's legislative affairs director. "It really is a way of him maximizing the opportunity to control all aspects of these efforts."

But the national security model is far from perfect, having produced memorable conflicts between White House advisers and secretaries of defense and state.

As national security adviser during President Bush's first term, Condoleezza Rice famously failed to resolve clashes among Defense Secretary Donald H. Rumsfeld, Vice President Cheney and Secretary of State Colin L. Powell.

Much depends on personalities, said Roy Neel, who was deputy chief of staff for Clinton. Bush's foreign policy arrangement was a "nightmare situation," he said. Far more successful, Neel said, was Clinton's creation of the National Economic Council with Robert E. Rubin stationed in the White House and serving as its chief.