Fighting has negative connotations but it is really about survival. On the streets, serious fights end quickly, in seconds. Trained fighters and martial artists say that to fight well, you must concern yourself with what is in your control and be in the present. In the present, you can take opportunities as they come and defensive action as you need to. Yes, a high level aggression is also needed.
They will tell you that in a fight, once you start worrying about what your opponent will do, you get hurt. Your focus shifts to anticipation and you begin to be led by the opponent, fighting your opponent’s fight. Your focus must therefore be on what you are doing with your strengths and abilities, in the moment. Fight your fight and let the opponent worry about theirs.
As Steven Covey would say, be in your circle of control. Do not dwell in your circle of concern, where you have neither control nor influence. This has application to daily life, individual achievement and competition between organisations.