The King's Indian Attack begins with 1. Nf3 Nf6 2. g3, a flexible setup that aims for piece activity and a strong kingside presence. In the position given by 1. Nf3 Nf6 2. g3 d5, Black has established a pawn in the center, securing control of key central spaces. White must decide how to develop while maintaining flexibility and the potential to attack in the middlegame.
Best Moves
The Sensible ♗Bg2
The move ♗Bg2 continues with the typical plan of the King's Indian Attack, where the fianchettoed bishop exerts pressure on the long diagonal. This move supports White's goal of maintaining a strong grip over the center and aims for flexible piece positioning. This approach allows for future central pawn breaks like ♙d3 or ♙c4 to liberate the bishop even further while providing increased control over the center.
Important Alternatives
The Preparing ♙a3
♙a3 offers a conservative approach to development, aiming to avoid any potential bishop pins on b4 or future pawn thrusts with b4. This move is not as dynamic as ♗Bg2, but it could prepare for a pawn push to b4, targeting Black's pawn chain and increasing space on the queenside, leading to a different type of middlegame struggle.
Critical Mistakes
The Passive ♙b3
♙b3 is considered a mistake in the position as it does not contribute effectively to White's setup and exposes the position by neglecting to control the center. It wastes a tempo that could be utilized to prepare ♗Bg2 or other important central plays. Furthermore, b3 creates weaknesses along the light squares and undermines potential pressure on the long diagonal.
The Errant ♘Nh4
♘Nh4 severely weakens White's position and coordination, offering little more than a tactical target for Black. The knight is awkwardly placed and could be easily pressured by moves like ♙g5, eliminating its influence altogether. This constitutes a significant blunder as it misplaces a knight without strategic compensation.
Conclusion
In the King's Indian Attack after 1. Nf3 Nf6 2. g3 d5, White should pursue sensible development aimed at building a strong kingside presence. The main move ♗Bg2 fits these plans perfectly, establishing a presence along the long diagonal while maintaining central flexibility. Though some alternatives like ♙a3 prepare gradual expansion, others, notably ♘Nh4, should be avoided to maintain harmony in the setup.