Space launch and ICBM technology has actually drifted apart over time. The early ICBMs that were suitable for space launch were liquid-fueled, and this is actua

Space launch and ICBM technology has actually drifted apart over time. The early ICBMs that were suitable for space launch were liquid-fueled, and this is actually a really bad choice for missiles; it can take hours to fuel a rocket and ready it for launch. Modern missiles are almost all solid-fueled, which lowers performance (bad for commercial launch) but lets you store the missiles fueled and ready for launch. The only example I know of an operational launch vehicle with a lot of ICBM commonality is the Israeli Shavit, and that one is not commercially competitive; Israeli payloads (even military) are only launched on Shavit if they require a particular level of secrecy.