The king on h2 justifies its position, as the black pawn queens without check! Black resigned.
The centre is closed, and the pawn chain b2-c3-d4-e5 is directed towards the kingside, so that is the side on which White should play, the side on which he has more space. The decisive factor in this is the control of various dark squares, especially f4. To seize these squares for his knight, White is prepared to sacrifice material.
Black is also worse after 17...gxh4 18.Nf4 Qd7 19.Bh3 0-0-0 20.Nxe6 Qxe6 21.Ng5!? Qg8 22.Rxf5 Kb8 23.Kh2+/=. Although the white king is exposed, Black cannot bring up any reserves to attack it, as his knights on b6 and c6 are virtually just spectators. This means that White effectively has two extra pieces on the kingside!
Unity Chess Club
Viswanathan Anand 2770 Michael Adams 2670 Madrid 1998 White to move
White has a bishop that has no good square. After his next move, however, such a square appears, and the black king is seriously weakened:
Unity Chess Club
Maxim Turov 2539 Valery Popov 2587 Russia 2006 Black to move
Black lands a blow at the most vulnerable point: