As grid expansion accelerates to meet data center, EV, and renewable energy demand, transmission structures face severe supply constraints. Lead times have stretched to 3-5 years for large power transformers, with limited domestic manufacturing capacity concentrated among few global suppliers. Rising steel and copper costs, specialized fabrication requirements, and permitting delays compound the bottleneck. Utilities racing to interconnect new generation and upgrade aging infrastructure risk project delays and cost overruns. Without expanded manufacturing capacity and standardized designs, transmission structures could become the critical chokepoint constraining grid modernization through the decade.