My definition of heroism is one of character. What you guys are talking about is circumstance. Many people with heroic character are never put to the test because they never find themselves in such a situation, but if they did, they would respond heroically because that is in their character. Just because someone who would behave in an heroic fashion if the need arose, but never has the opportunity to do so, does not make them any less heroic. I think Ariana's gesture is indicative of heroic character and, if she was put to the test, she would respond heroically. You don't have to bash down doors with an automatic weapon or perform emergency surgery in the street to be heroic.