Why were the concentration camps not military targets?

If you are talking about the German camps, then it's because the Allies were not exactly aware of the camps, and the Germans routinely transferred the prisoners around to hide them.

The Allies had to get far enough inland to find them, which means they would have to be either flying over without being shot down by anti-aircraft, or they would have to somehow make it past the traps and guards to find them.

Either way, they would need to make it past the Germans to actually find them and know of their existence.

If you are talking about the Japanese camps after Pearl Harbor, then it would be because of the guards and barbed wire. Plus, who would want to go through the trouble of breaking into the camps in the first place?

Explanation:

sitting in that one chair where he could get shot at was his worst decision.

you didn't post an image.