As soon as the Colonel stopped the countdown, the barrier that was protecting the base was now broken. The Titans were already shooting at the base and at the ships in front of them and now the IGT Fed's fighting crews also engaged in the fight.
All of the ships that were lining up in the sky were now aiming at the missile launchers of the enemy warbirds and were trying to destroy them. There were two launchers at the bottom of that warship and two at the top. And the crafts were aiming at those launchers and were firing their own missiles at the enemy.
That was the best move they had in order to win this fight because completely destroying those large ships using the small fighter crafts was completely out of the question.
Alexis, on the other hand, was clearly being aimed by the leader's ship. It was firing at Alexis as if that leader was holding a grudge against Alexis for putting several holes in his body.