IIRC, in the current version of RA, it stated the SLBMs are demos only. They are beautifully modeled, have stage separation and enter space, but the re-entry and detonation are not written or modeled.
The closest you'll get is with the other rival mod, Alfa Tau. It has fully functional SLBMs that will reach their targets and destroy all targets their warheads would cover. However, due to limitations, they don't go suborbital, and only top the cloudcover. They also don't separate, nor satisfy the player with a mushroom cloud, since that's not modeled. All surface targets simply explode within the detonation radius.
Ideally, a merge of the two routines and models would be more satisfying in one mod, but even then there's no visual payoff at impact. Just the tactical win.
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