'Mini-nukes', 'preventive strikes'...: myths and realities of the US nuclear policy

According to many press comments, the US nuclear posture review would foresee the use of non-strategic nuclear weapons of very low energy ('mini-nukes'), also for preventive purposes, in particular for the strike of shielded or buried military facilities (Robust Earth Nuclear Penetrator, RENP). In fact these comments make a confusion between two distinct measures: one concerns the weapons penetration problem, while the other concerns the search for new future nuclear concepts. This short article tries to unravel this complex question. (J.S.)