The US defense innovation system enjoys tremendous advantages that other countries cannot readily replicate. It has accumulated capabilities over decades of funding and experimentation that dwarf other countries’ efforts, and the incentives to innovate in the United States are not easily replicable elsewhere. The unique US political system favors substitution of technology for labor, openness to new ideas, and competition among decentralized organizations to solve national security challenges. The constant worrying that the United States is losing its defense innovation advantages is simply part of the politics that keep the United States far, far ahead of its potential rivals...