In a non-MAD employment scenario, you would build them for area denial. e.g. I don't really know how far the fallout would go from some cesium nukes, but maybe

In a non-MAD employment scenario, you would build them for area denial. e.g. I don't really know how far the fallout would go from some cesium nukes, but maybe if russia wants a moat that lasts a long time but they can't take over ukraine with conventional forces, then they could launch some at ukraine and build their moat that way. In a MAD scenario, I would view them as a bigger scarier stick to threaten people with.