how does one become a diplomat, especially if you are older and looking for a second career. I have an MBA?

Answer 1

Apply in the foreign service of your country so that you could be appointed as a consul or ambassador. However, you need to know more politicians because they have the appointing power.

Answer 2

If you are American you would have to apply with the State Department. There are several opportunities w/ the State Dept. regarding work as a diplomat/ambassador etc.

You would also have to take a test to become a Foreign Service officer. The process is quite lengthy as well as detailed because of security clearance.

http://www.state.gov/careers/