The Collaborative International Dictionary of English v.0.48:

Strategist \Strat"e*gist\, n. [Cf. F. strat['e]giste.]
   One skilled in strategy, or the science of directing great
   military movements.
   [1913 Webster]

WordNet (r) 3.0 (2006):

strategist
    n 1: an expert in strategy (especially in warfare) [syn:
         strategist, strategian]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "strategist":
   Machiavellian, a, architect, behind-the-scenes operator,
   calculator, contriver, designer, developer, deviser,
   eminence grise, enterpriser, entrepreneur, finagler, framer,
   gamesman, gray eminence, intriguer, kingmaker, logroller,
   machinator, maneuverer, manipulator, operator, organizer, planner,
   pork-barrel politician, projector, promoter, schemer, strategian,
   tactician, wheeler-dealer, wire-puller