Rocket launcher script help

Hi, I have a fps and I have an enemy robot attack any object that has the tag player. (other objects have the tag player as well) I have a rocket launcher object and script that are children of the robot. Here is the first script:

RocketLauncher.js

    #pragma strict
     var projectile : Rigidbody;
     var initialSpeed = 20.0;
     var reloadTime = 0.5;
     var ammoCount = 20;
 
     private var lastShot = -10.0;
     
     private var cc : CharacterController; 
     var player : Transform;
      
     function Start() {
         //var go = GameObject.Find("First Person Controller");
         var go = player;
         go = GameObject.FindWithTag("Player").transform;
         player = go.transform;
         cc = go.GetComponent(CharacterController);
      }
      
      
      
     function Fire () {
         // Did the time exceed the reload time?
         if (Time.time > reloadTime + lastShot && ammoCount > 0) {
            // create a new projectile, use the same position and rotation as the Launcher.
            var instantiatedProjectile : Rigidbody = Instantiate (projectile, transform.position, transform.rotation);
      
            // Time of flight to reach player
            var t = (player.position - transform.position).magnitude / initialSpeed;
      
            // Project future position
            var futurePos = player.position + cc.velocity * t;
      
            // Aim and fire at that future position
            var aim = (futurePos - transform.position).normalized;
            instantiatedProjectile.transform.rotation = Quaternion.LookRotation(aim);
            instantiatedProjectile.velocity = aim * initialSpeed;
      
            // Ignore collisions between the missile and the character controller
            Physics.IgnoreCollision(instantiatedProjectile.collider, transform.root.collider);
      
            lastShot = Time.time;
            ammoCount--;
         }
     }

It tracks the target the points the rocket the right way then fires. It works fine until the robot kills target which is the same object that is assigned to the player variable. Then the rockets don't go anywhere and i get an error. I want the robot to send its target value to the launchers target value. Can someone please post a revision of the code? Thank you in advance.