It's the climax of a science fiction film. The captain tells them that he will make the preparations. He breaks contact and then turns to the second in command. The two of them flip the protective flaps on their control panels and both press the finger-print activated buttons together.
Self destructing a space ship is never that easy.
What really happens is that the captain has to ask someone in engineering to initiate the self destruct sequence and then it takes several long minutes with spoken countdowns, dimming lights and in the final stages plenty of sparks and shuddering. We need time to think about this, you are free to go. In the last issue I wrote about powerful functions and what happened when they were used in error. Well, many powerful functions are so powerful that their use needs to be made artificially complex so that accidental use is minimized. Think of the safety catch on a fire extinguisher.