A Positional Game (or Why Is Chess 99% Calculation)

In this game I went for a safe setup with White - with the idea to first secure my king and only afterwards play at the middle of the board. I was to quickly castle kingside and then react to Black's pawn center or, given the opportunity, create one of my own. The game was very balanced, with an equal middlegame and a calm strategical buildup. Although there were no sharp attacks, the positions were rife with tactics. My opponent failed to see one, which cost him a pawn and eventually the match. After simplification I went into an endgame with an advantage of a pawn plus a good vs. bad bishop, and Black resigned shortly thereafter. Here's the game: