Why might a pointlight not come back on when re-enabled after being disabled?

I have a pointlight in a prefab gameobject missile. The first time I use the object, the light works. Next time, it does not, though the editor shows the light to be becoming active in the hierarchy view, and correctly placed.

• I have a projectile prefab with a point light attached. In the projectile script, I have an explosion prefab instantiated.

• I create 5 instantiations of the projectile and store them in an array. I loop through the array as I am firing the projectiles, and am careful not to fire missiles that are already in the scene.
  

• When a projectile hits something I turn off its renderer and start an explosion. When the explosion is finished, I Setactive = false on both the missile and the explosion.

• when I fire the projectile, I Setactive=true and turn its renderer back on.

• The first 5 missiles I fire, the light works fine. But on subsequent shots with the same missile I get the missile, but not the light. The editor, however, shows the light to be active and correctly placed on the re-activated missile(s).