Yí ge hǎo de jūnshìjiā bùguāng huì dǎzhàng, hái yào dǒng zhèngzhì.
A good military strategist doesn't just know how to fight; he has to understand politics too.
Tips
usage
The suffix 家 marks a recognized master of a field: 政治家 (statesman), 科学家 (scientist). So 军事家 is a title of distinction for figures like 孙武 or 拿破仑, not a word for an ordinary officer.