the current range of loitering munition are less than 100km, most of them being less than 20km, unless the enemies are stupid, no one can get to that range of a S400 site.
the IAI Harop race is 1,000 km, we saw them being used on S300 batteries in the Azeri Armenian conflict
Other missile defence systems is and will be deployed at the borders.
its a terrible idea to deploy anything on a border, as its far too exposed, SAM systems are always placed further back to protect from SEAD measures.
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