Stonewall Attack

The Stonewall Attack is a chess opening; more specifically it is a variation of the Queen's Pawn Game. It is characterized by White (generally) playing his pawns to d4 & e3, playing Bd3, Nd2, and then playing Pawns to c3 and then f4; although the moves are not always played in that order, (see transposition). The Stonewall is a system; White heads for a very specific Pawn formation, rather than try to memorize long lines of different variations. If White puts up the Stonewall formation it is called a Stonewall Attack, regardless of how Black chooses to defend against it. When Black sets up a Stonewall formation, with pawns on c6, d5, e6 and f5, it is (then) a variation of the Dutch Defense. MCO-15 gives the following as a main line: 1.d4 d5 2.e3 Nf6 3.Bd3 c5 4.c3 Nc6 5.f4. (See page #511 and column #9.)

As the name implies, the Stonewall setup is a solid formation which is hard to overrun by force. If Black fails to react energetically to the Stonewall setup, White may launch a lethal attack on the black king, typically by playing the knight from f3 to e5, advancing the g-pawn to drive away the defending black knight, and making a well-timed bishop sacrifice at h7 (see Greek gift sacrifice) when White can bring one of the major pieces (queen and/or rook) to the h-file. Often this attack is so powerful that White does not need to develop the knight on b1 and bishop on c1. Traditionally, chess computers have been vulnerable to the Stonewall because the positions are usually without clear tactical lines. White simply prepares for an assault by bringing pieces to aggressive posts, without making immediate tactical threats. By the time the computer realizes that its king is under attack, it is often too late. This, however, is not the case with newer chess computers.

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