You may have heard that if we were to throw away an airplane every time we fly on one, then air travel would be horrendously expensive. The fact that we re-use airplanes after using them, helps keeps costs down.
This thinking has recently been extended to reusable rockets. By making rockets reusable,
they are now much less expensive to launch than before.
Likewise, if we throw away an ICBM every time we use one, then it makes WW3 much more expensive from an arms budget standpoint. What's needed are reusable ICBMs.
The idea is that the ICBM is composed of a rocket booster which lofts the warhead up high in the sky, separating and releasing the warhead payload which then reaches apogee before coming down on its target. The separated rocket booster can then retropropulsively land back on the ground, and be readied for re-use.
This can help lower the costs of WW3.
(We won't worry about how to make WW4 cheaper, since that war will only be fought with sticks and stones.)