This position had already occurred a couple of times in practice. White did not manage to win a single one of these games, and indeed Black appears to have a safe fortress. Obviously White will not be able to create a passed pawn on the queenside. Without that, making progress on the kingside turns out to be impossible.

Looking a little further, it will help if you start searching for ways to keep the h4-knight off-side.

After the text move, the rook and passed pawn turn out to be a dangerous couple in exchange for the two pieces, which is not so strange especially if you consider the knight on h4 – another reason not to go for this knight immediately.

White resigned.

No! With his last move White set a disguised trap, protecting the g5-bishop and taking control of the a5-square. Have you got the clue? Look what happened in the game:

Caught by surprise!

Black resigned.

After 17…Qxc2, White not only has great positional compensation for the pawn, but he can also win material straight away: 18.Rf2 Qc5 19.Rc1 Qd4 20.Nc7.

And Smyslov used his great knight on d5 to launch a decisive attack on the kingside: