Global fiber supply gap to hit 180M core-km in 2026, spot prices up 2.8-5x

The fiber squeeze is no longer a telecom-capex story but an AI-infrastructure one: the same data-center and interconnect buildout lifting compute demand is now colliding with a physical input that takes years to expand. The shift from spot buying to long-term contracts is the tell — vendors are treating supply security, not price, as the binding constraint, which tends to entrench the shortfall rather than resolve it. The read-across is to any RWA or infrastructure thesis that assumes connectivity costs keep falling. Whether the projected tightness through 2028 holds depends on how much new fiber capacity actually gets financed and commissioned.