I think that nothing is impossible when you want to fulfill a dream. A lot of people will tell you that you can't do it, that you don't have what it takes, but if it is in your heart and you feel it, there is nothing that will stop you. It is like the sun - you can't block it: it will shine regardless, if that is what you want.
Ultimately, leadership is not about glorious crowning acts. It's about keeping your team focused on a goal and motivated to do their best to achieve it, especially when the stakes are high and the consequences really matter. It is about laying the groundwork for others' success, and then standing back and letting them shine.