judo,taekwondo,both olympic sports

why not karate?

There may be several reasons. However, probably the most significant reason for Karate's repeated denial from the games is that it is too political. Ok, so martial arts and politics don't sound like they go together. Well, let's break it down.

First, there are hundreds of variation of Karate around the globe. Some are very similar with only slight variations while others are completely different. For illustrative purposes, let's compare the evolution of Karate to religion. Over thousands of years, Christianity has changed. It has broken in to hundreds of subsects - Baptists, Catholics, Protestants - they are all Christian. The same is true of Karate. The problem is that each style, as similar as they may be, there are disagreements about the "correct" execution of various elements of the martial art. By choosing one Karate organization over another, the IOC risks implying that one style is superior or more correct than another.

Another problem is that once the residing organization is choosen, competitors, regardless of style, will have to design their training to match the expectations of the Olympic games. The problem is that many students will spend years and years perfecting their art only to be told that they need to "start from scratch" to learn techniques that conform to Olympic guidelines.

there we go

There may be several reasons. However, probably the most significant reason for Karate's repeated denial from the games is that it is too political. Ok, so martial arts and politics don't sound like they go together. Well, let's break it down.

First, there are hundreds of variation of Karate around the globe. Some are very similar with only slight variations while others are completely different. For illustrative purposes, let's compare the evolution of Karate to religion. Over thousands of years, Christianity has changed. It has broken in to hundreds of subsects - Baptists, Catholics, Protestants - they are all Christian. The same is true of Karate. The problem is that each style, as similar as they may be, there are disagreements about the "correct" execution of various elements of the martial art. By choosing one Karate organization over another, the IOC risks implying that one style is superior or more correct than another.

Another problem is that once the residing organization is choosen, competitors, regardless of style, will have to design their training to match the expectations of the Olympic games. The problem is that many students will spend years and years perfecting their art only to be told that they need to "start from scratch" to learn techniques that conform to Olympic guidelines.

there we go

Spot on there fella, it's a bit like religion, there are dozens of groups that all think their way is the correct way, and that all the others should be poo pooed,

I always thought it was because Judo is a sport, and not a martial art such as karate.

Slightly off topic, but I read that golf and rugby are in the 2016 Olympics