Leadership on the Mind

I was reading a little bit of lifehack.org the other day and ran across this article on leadership.

The article is an interesting read, but what struck my attention was this paragraph:

Leadership seems to be on everyone’s minds one these days. Educators talk about “teaching leadership”, religious and charitable organizations host “leadership development” programs , businesses invest heavily in “leadership training”.

It's true isn't it? Everywhere you look seems to be someone else doing leadership training or developing leaders around them etc.

Is this a relatively new thing? It seems that is has been around most of my life but then I'm only 22.

Is the leadership development stuff we do today formalizing informal things from the past?
Is it something new that we had over looked? A passing fad?

Any thoughts?