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Looking for 50+ year old sci fi book. The Dulgari (sp?) empire has the humans on the run. The hero is a military man who has battled the Dulgari. There are always more of their ships than ours. The initial battle he goes through a series of pre-programmed ship movements, to a draw. Ends up tricking aliens to bring fleet to earth. He signals a "drive mechanism" to start that blows up sun and destroys their fleet and give humans advantage. I remember there being a drink called the "9 Planets".