President Bush on Friday nominated Air Force Gen. Richard Myers to be chairman of the Joint Chiefs of Staff, the nation's top military position. During a press conference in Crawford, Texas, Bush praised Myers, the current vice chairman of the Joint Chiefs and former head of the U.S Space Command, as a man of "steady resolve and determined leadership." "Gen. Myers understands that the military's strength lies in its people and in its technological superiority," Bush said. "The chairman of the Joint Chiefs of Staff is one of the most important appointments a President can make; Secretary [of Defense] Rumsfeld and I thought long and hard about this." The chairman of the Joint Chiefs of Staff is the principal military adviser to the President, the Secretary of Defense and the National Security Council. "No one will have a greater responsibility than he to turn your vision into reality for the 2 million-plus men and women who don our nation's uniforms to carry out their vital assignments," Rumsfeld said to Bush during the briefing. The nomination comes at an important time for the military. The Defense Department is undergoing its Quadrennial Defense Review, an exhaustive internal study conducted every four years that looks at everything from threats the U.S. will face in future wars to whether military forces and bases need to be downsized. The review is due to Congress Sept. 30 and will be used as the Bush administration's blueprint to transform the U.S. military for the 21st century. "The Defense transformation is a process, not a one-time event," Bush said. "The decisions we make-or put off-today will affect the national security of tomorrow." Bush also nominated Marine Corps Gen. Peter Pace, commander of the U.S. Southern Command, as vice chairman of the Joint Chiefs of Staff on Friday. Myers, who was a fighter pilot during the Vietnam War and has also served as a commander of U.S. forces in Japan and Hawaii, replaces current Joint Chiefs Chairman Army Gen. Henry H. Shelton. Shelton plans to retire at the end of September. "I figuratively and literally have enormous shoes to fill," Myers said, referring to Shelton's departure. "As the vice chairman, Dick has been a crucial and indispensable part of the national security team for the past two years and is well-prepared to meet the challenges of this high office," Shelton said. If confirmed by the Senate, Myers would be the 15th chairman of the Joint Chiefs of Staff. The Joint Chiefs of Staff consist of the chairman, vice chairman, chief of staff of the Army, chief of Naval operations, chief of staff of the Air Force and the commandant of the Marine Corps.