Playing in column 4 is strategically strong because:
1. It builds on my center control (I already have a piece in column 3)
2. It creates a potential horizontal threat with my existing piece
3. It prevents my opponent from easily expanding horizontally from their piece in column 5
4. Center control is valuable in Connect Four as it provides more potential winning patterns
5. This early in the game, positioning in the central columns offers the most flexibility for future moves