Why is Karate not an Olympic sport?

The main reason is the same as kung fu, there are many different styles and then there is the profound difference between traditional and sport karate ... then there are several federations and this involves a problem for the organization.
In Italy, the bigger karate federation is call  fijlkam and here we can find the greatest champions of WKF federation, where we can find professional athletes paid to do karate by the armed forces, such as police, etc..
The Biggest problem is that a lot of very important masters of traditional karate doesn't want to mix all  different style,  and find new rules that can be included for the challenge, from Kata to Kumite. 
Some of the most important master are japanese, below some of them:


M° Hiroshi Shirai, black belt 9° Dan, was sent to Italy to export the Traditional Karate.

Taiji Kase was sent to France to teach karate, 10° Dan

Hidetaka Nishiyama 10° Dan was sent in USA, On 3 November 2003, the Emperor of Japan awarded him the Order of the Sacred Treasure, Gold Rays with Rosette to Him in a ceremony on the grounds of the Imperial Palace in Tokyo.

Hirokazu Kanazawa (金泽 弘 和, Hirokazu Kanazawa, May 3, 1931) is a Japanese karate master, and Karateka. It is considered one of the greatest karate masters never existed. In 1956 he passed the examination for the 3 rd Dan and examination for trainer. In 1957 he participated in the tournament for the first time All Japan Karate Championships. On that occasion, Kanazawa had a broken wrist and was about to give up. Meanwhile, the mother was already traveling to come see him, so he decided to participate anyway and managed to win all matches. Since then won the tournament for two consecutive times.

Kanazawa is currently president and chief instructor of the world's largest Shotokan Karate organization in the world, the International Shotokan Karate-do Federation. In April 2000 he was promoted to 10 Dan in spite of his fame and success, Kanazawa is a very helpful and charismatic person and prefers to spend most of your leisure time with their students. It is also 2 Dan in Judo and practice Tai Chi Chuan and Kobudo.