Historical clue formulations

• Snoopy's nemesis — 2023-11-21
• Snoopy's imaginary antagonist — 2023-04-12
• W.W. I fighter pilot who is Snoopy's fantasy opponent — 2019-12-02
• W.W. I enemy ace — 2018-07-17
• Famed Fokker flier — 2010-08-01
• Famed aviator — 1998-12-06
• Strip's bête noire — 1997-11-23