Reflections on Chiral Symmetry within QCD

That chiral symmetry is a crucial feature of the strong force was realized before the discovery of Quantum Chromodynamics. However, the full power it exerts on the structure of the nucleon became apparent only afterwards. We present a high-level and somewhat personal overview of its role in almost every aspect of proton structure, from its mass and spin to the asymmetry of its antimatter content and its strange quark content. The lessons learned from studying the proton are also vital with respect to the modern challenge of the nature of baryon excited states.