I am reading a lot about this subject and I suppose the driving force is I now have a son in college. I wonder what he will want to do ultimately with his life. As I read I see some common threads in tomorrow's leaders no matter what discipline they are in (so, these apply to supply chain people).
First, learn languages! This is an absolute must and one which is tough for Americans to get their arms around. If you cannot speak at least one other language other than English you are essentially toast. Two or three are even better. The best people I see in business today are very comfortable moving between languages.
Second, be prepared, willing and excited about moving globally. I met a person the other day who had run an operation in Russia, is now in China, travels frequently to the US and is a German national. OK, you may not be able to do all that but understand that is who you are competing with. Unfortunately, most people elsewhere in the world are far more comfortable doing this than Americans are.
Third, be a leader. It just does not matter what you do (unless you are going to be a highly skilled technocrat / individual contributor your entire life. No matter what you do in life, you will need to be a leader.
Fourth, never stop learning! When I interview people I ask what book they most recently read and you would be amazed how many really cannot remember one or if they did read it, it is clear they just skimmed it. Reading things such as the Harvard Business Review, The Economist, The NY Times and The Wall Street Journal are a must. Put down the remote, turn off the T.V. and read!
These are just a few of my thoughts on this topic. There are a lot more I know. I wanted to get these out fast.