America's defense-tech startups are building advanced weapons faster than ever, but the fragmented, aging supplier base can't scale production to meet demand. The article argues that private capital and better engineering partnerships between systems companies and manufacturers are essential to close this gap—and that the Pentagon needs to commit to buying these systems to make it economically rational for suppliers to invest in capacity.

• 95% of American machine shops employ fewer than 50 people and were built around low-volume, high-precision work; they can't absorb sudden production ramps without massive upfront capital investment and government demand certainty.
• Defense contractors like Anduril have hit the limits of what private capital can finance for speculative production capacity—suppliers need actual purchase orders from the Pentagon, not just promises, to justify tooling and hiring.
• Current supplier relationships use "build-to-print" models where manufacturers just execute drawings; the next generation needs co-engineering where suppliers redesign components and production methods together with systems companies to cut costs and enable scale.