I don't believe they are the same.
The S-400 requirement was actually separate from the ER/XRSAM system, 'cause it's BMD capable, so it has radars and other systems specific to that role as well, not just air defence. But it works in our favour to replace the S-400 with an Indian equivalent.
Anyway...
I’ve become increasingly intrigued by the fact that western military analysts – even among those not burdened with the epidemic strain of virulent antipathy towards Russia – have not spoken much (if at all) about what I consider to be quite arguably the most impressive revelation of the war in...
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