I'm sure now, you have not seen those drawings, what military planned to do with silo infrastructure. They planned to make constantly working build system, so

I'm sure now, you have not seen those drawings, what military planned to do with silo infrastructure. They planned to make constantly working build system, so would be tens more silo's than real ICBMs, and they planned to constantly move ICBMs, so nobody will know, in which silo now exists ICBM, and which is empty, and they planned to build silo's from underground, so they will open just before ICBM launch.