特朗普回应奥巴马称相信外星人存在：他泄露机密 犯了大错

Group 1 - Trump's response to Obama's comments on aliens indicates a belief that Obama leaked classified information, which he considers a significant mistake [1] - Obama stated in an interview that he believes aliens "exist," but later clarified that he has not seen any evidence of contact with humans during his presidency [1] - Trump's uncertainty about the existence of aliens reflects a cautious stance on the topic, avoiding a definitive statement [1]