I believe that all candidates proposing to apply for such a position should complete a course at a university on the geo political status, diplomacy and ethics as well as geography. Must know where North Korea is before you want to bomb it.
This would prevent trouble like we have at the moment where the elected president wouldn't have a clue in any of these attributes.
People in countries outside of the United States are shit scared of anything that Trump does in regard to foreign politics. For example. Recently he goes to Israel and lets the Israeli prime minister make Jerusalem the capital of Israel. There were enough tensions between them and the Palestinians as it was.
Oprah would not have the qualifications. This is in no way to say that she is not a nice person.