The ICBM interface corresponds exactly with nuclear operator control booths of that era, and in fact, one of the game's strengths is its high historical fidelity. You can interact with all the displayed elements in two ways: with a left-click you can view a certain control and with a right-click you can use it.
ICBM has also paid great attention to realism as far as the conduct of your character is concerned. This means that not only can you not activate a nuclear missile whenever you want, but you can't even roll up your shirtsleeves (which would fall outside normal procedure).
ICBM is an excellent simulation game that has both an exciting premise and absolutely delightful graphics. A game worth playing if only to look at the screen and watch what happens. And trust us, a lot happens.