If it can orbit a satellite it can put a warhead anywhere on Earth

The NORKs just launched an Earth satellite.  If your rocket has the delta V to achieve orbit, it can put that "satellite" anywhere on Earth.  I haven't heard just how heavy the NORK satellite was, but it's a start.  A helova start.  To have an ICBM, the payload has to be enough to carry a nuke.  We think, we don't know for sure, that the NORK nukes are "first generation" i.e. heavy, weighing a matter of tons.  Back in the fifties, when both we and the Soviets were getting into the ICBM business, the war heads would be first generation and be very heavy.  The Americans decided that the necessary rocket to hoist a first generation nuke would be ridiculously huge and so we didn't get  seriously to work on a missile until the later generation of nukes came along with weights down into the 100 pound area.  The Soviets wanted a missile so badly that they set to work to build the ridiculously huge rocket.  That rocket came on line about 1957. launched the first Sputnik, and did all the Soviet space launches for the entire Cold War.  We didn't come up with anything to match it until Saturn 5 in 1968.