After I have built either a missile silo or airstrip, I can't use them? Like, missile silos, I have nukes and all requirements for the silo, and the military engineer can and does build them, I just don't get the option to use them? There's no red button above it telling me how many (thermo)nukes I have, no button to fire them. And the airstrips don't display plane slots or anything, I simply can not use them for some reason?