WASHINGTON, Dec. 28 (Xinhuanet) -- U.S. President George W. Bush on Wednesday changed Pentagon's line of succession, pushing three military service chiefs beneath three civilian undersecretaries.

    The change was announced in an executive order signed by Bush during his holiday vocation.

    Pentagon Spokesman Bryan Whitman said the three undersecretaries were promoted because they have "a broad knowledge and perspective of overall Defense Department operations" while the service leaders are more focused on training, equipping and leading a particular military service.

    U.S. military observers said the change makes it easier for the Bush administration to assert political control of the U.S. military.

    Under the new plan, Stephen Cambone, the undersecretary for intelligence, moved up to the third spot while undersecretary for policy Eric Edelman and the undersecretary for acquisition KennethKrieg hold the fourth and fifth positions.

    The first to succeed Defense Secretary Donald H. Rumsfeld remains the job of the deputy secretary, a position currently vacant because the Senate has not confirmed Bush's nominee--current Navy Secretary Gordon England, who is also the acting deputy secretary.

    The new succession order bumps the Navy Secretary to near the bottom of the line of succession -- eighth behind the deputy secretary, the three undersecretaries and the Army and Air Force secretaries.

    The Army Secretary historically has been third in line, right behind the deputy secretary.

    The U.S. Army was once considered the backbone of the nation's military.

    However, since the Sept. 11 terror attacks, intelligence gathering has taken center stage. Enditem