To face the central tension, White has three options :

3. e5 closes the game. The pawn structure looks like a French Defence without the blocking Black's light square bishop.

3. exd5 simplifies the game, but won't prevent Black from playing e5.

3. Nc3 increases central tensions, which can be released with 3...dxe4 or maintained with 3...e6 (transposing to French Defence).

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'1. e4 Nc6 2. d4 d5'

Wikipedia has related information at Nimzowitsch Defence.

• Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.