To defeat an action or plan means to cause it to fail. The navy played a limited but significant role in defeating the rebellion = thwart
win a victory over; "You must overcome all difficulties"; "defeat your enemies"; "He overcame his shyness"; "She conquered here fear of mice"; "He overcame his infirmity"; "Her anger got the better of her and she blew up"
the feeling that accompanies an experience of being thwarted in attaining your goals