Hi @tydynrain - that's a very good question. In chess, there are white "openings" such as the "Queen's Gambit" and then there are black responses, or "defences" in response to white's opening. Charlie Storey's original "Sniper" book is about a black "hypermodern" defence to a variety of white openings - so it is a versatile repertoire.

Now, to directly answer your question - "why can this type of play only be used with black?" - actually, Charlie Storey later developed what he called the "White Sniper" where white opens with the same three moves. So this opening can be played by White although I haven't tried it.
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