Hall of Infinite Doors

Good job. They had considered integrating naval units into the game but that idea was abandon early in production. Your next question is:

Who is the Terran protagonist who shows up in every single campaign in both Starcraft and the Expansion Brood War?

His picture is shown below. Edit: Well... it was. Apparently the link is broken. I'll fix this later. For now, a hint, his initial rank is Marshal and he has a big crush on Sarah Kerrigan early in the game.