Are leaders born or made?

I had the opportunity to hear a gentleman speak on the 12 essential behaviors of good leaders. He was with an organization called Leader's Summit. There were some good things, but also some things I didn't really agree with. He had these essentials divided into 6 "hard skills" that he said are "what a leader does" and 6 "soft skills" which are "who a leader is." So far, so good. Except that several of the soft skills were redundancies which seemed to be splitting hairs and making it more confusing than it needed to be.
But it was still quite interesting. He gave us a chance to interact, call out our answers, and ask questions which I always enjoy. (But I always get a little worried when someone wants the fact that he reads 50 books a year to be included in his introduction.)
One question he asked us to discuss is "Are leaders made or born?" The two women in my huddle said "made" but I say leaders are both born and made. When he finally gave his answer it was most unsatisfactory. Not definite or helpful at all. (I wonder why he asked if he didn't really have a strong point of view on the topic.)
When it comes to leaders, I am convinced that genetics plays a role as certain personality mixes seem more pre-disposed for leadership. More leaders are either Dominant or Inspiring relational types. I'm also convinced that birth order plays a role as well as upbringing - more leaders grow up in homes where either the mom or dad (or both) was a strong leader. Naturally, early opportunties to lead increases the liklihood and then, of course, spiritual gifting trumps them all.
Our teacher today also emphasized that anyone can become a really, really good leader. That all the 12 behaviors/skills could be learned by anyone. I wonder if he was simply trying to sell his training seminars....whatever. I couldn't disagree more.
For years I used to believe that anyone could become a good leader, but no more. I believe that anyone can become a better leader than they are. But I do not believe everyone can become a really good leader.
First of all, character is the bedrock essential for good leadership. Alan Simpson said "If you have integrity nothing else matters, if you do not have integrity nothing else matters." A person can move others to action through the leverage of her position, or through fear or manipulation, or by paying big sums of money- but people only willingly follow someone who has proven that she will do what she says she will do and who is who she says she is.
I do not believe we can train someone to have integrity - not past the age of 30 anyway. Only God can change a person's character once deception has become a behavioral pattern.
Secondly, I have worked hard to develop people who I believed were leaders only to discover over time that they really lacked the inner drive to improve and change things that all leaders have. I don't believe anyone can teach that internal strong bias toward action that is the driving engine in every leader.