[6] At Pritzker Military Museum and Library, Clarke first served as Vice President of Administration and Operations.

He began producing and hosting episodes of Pritzker Military Presents and Citizen Soldier,[7] the library's two web and television programs.

[9] While at the Pritzker Military Museum and Library he created, and was one of the architects of the World War One Centennial Commission's 100 Cities/100 Memorials matching grant program sponsored by the Pritzker Military Museum and Library that helped communities across the United States renovate World War One monuments.

[14] In 2003, Clarke received Columbia College’s Paul Berger Arts Entrepreneurship Award for "outstanding not-for-profit management".

[4][16] Also in 2004, Mayor Richard M. Daley appointed Clarke to the advisory board of the City of Chicago Department of Cultural Affairs.