Drifting is a form of motorsports. But not a form of racing. (the drifting as we know it in LFS). Motorsport is not necessarily racing. Racing is motorsport though.
Racing: completing a certain distance, an amount of laps or over an amount of time with the goal of finishing first and/or as fast as possible. Drifting lacks this goal. Because the fastest way around the track is never by drifting except with rally or hillclimb. And even then it's used as a cornering technique only.