There are a lot of people who studied that and wrote about the world leaders over the history. My ideas of who would be the greatest world politician is likely burrowed from other writings or quoted from other people during my periods of awareness. Many times as well words comes to me like an inspiration by a higher power or I imagine so:
1- You need to be humble and I can repeat that until people stop me or I get sore throat. People would love to see a humble person go up and succeed. In that same time they would love to see an arrogant person to fall on his teeth.
2- You need to believe that you are humble. Your brain is the collective thoughts of a lot of people that you may not even recall their names. You need them again and again in order to think right.
3- consensus is always the way to go. The greater politician you are is the greater the diversity the people who are forming the consensus.
4- You should have the personality. You just have to have it. If you are selfish person in your personal life you just can not convince people. Great leaders are great persons to start with.
5- You need to have the humor. A person with no humor is a dry person. It is important to do it right in the dose, quality and with no humiliation to any person. I call it the genius of humor.
6- You have to win people minds and hearts. You just do not have an alternative you can not ask for their hands if you did not win their hearts and minds.
7- You need to have a strong personality. People can differ of what they look in a strong personality. For me I consider it the power of consensus. You make a strong decision when you have a great consensus and you convince people very well of your decision after you lay honestly all the facts and arguments.
8- You need to be a principled person but in same time you need to learn to compromise of what you think that it is still right and ethical to do it.
9- You need to be diplomatic in how to differ without criticizing and how to circumvent when you attack. Do not personalize anything. Even God hates the sins and not the sinners.
10- You have to always believe that your worst enemies can be your best friends. People change and policies change, this is the reality of life.
11- Always find common grounds like humanity. If you to find the common grounds first it becomes easier to solve the differences.
12- Be always honest it is the best medium of exchange. You commonly remember facts and not lies and you look very confused when you are quote on a lie. If you are a professional liar people will ultimately know that.
13- You have to anticipate criticism and shrug it off. It is part of the deal. If you are in politics for a great cause you will always consider the message more important than the messenger.
14- Last but probably first win the Jews. It is not only because they are in top of media, politics and finance but more so because a true Jew is a hero. Forget about the misconceptions of the Arab world. A Jew is the one who loves to fight for a good cause and the most to appreciate the word "Humanity".