I just watched a special on the History Chanel about Abraham Lincoln. The key thing on which they focused was that he struggled his whole life with depression. He had suicidal thoughts and struggled daily with the weight of his job as president.
What strikes me, is that we often gloss over the deep struggles of our leaders and instead focus on their shining moments. We see Moses confronting Pharaoh, not Moses shepherding flocks for 40 years while he deals with his rejection and fall from power. We see David slaying Goliath rather than David in a tomb, acting like a crazy person so that he can save his own life. We see Paul preaching and writing amazing messages rather than a lonely, man who is rejected and feared by everyone spending three years alone in the wilderness.
It is good to remember that the greatest leaders are those who have struggled greatly with themselves so that when external struggles arise they are equipped to succeed.
How are you struggling with yourself? Don't worry about how that might prepare you for the future, rather enter the struggle with all your might knowing that your first, your only battle is the battle for your soul. It is in this fight that you become a tool which God can use in his work as he fights for his kingdom.