Wilkerson spent some years in the United States Navy's Pacific Command in South Korea, Japan and Hawaii, where he was well regarded by his superiors. These recommendations led in early 1989 to a successful interview to become the assistant to Colin Powell, who was then finishing his stint as National Security Advisor in the Reagan administration and moving to a position in the United States Army Forces Command at Fort McPherson. He continued this supporting role as Powell became Chairman of the Joint Chiefs of Staff through the Gulf War, following Powell into civilian life and then back into public service when President George W. Bush appointed Powell Secretary of State.