For much of the 2000s and 2010s, electromagnetic railguns were touted as the future of naval warfare. The U.S. Navy envisioned railguns supporting long-range naval fire support, anti-ship warfare, and eventually even missile defense. The engineering turned out to be much harder As promising as the demonstrations were, turning a laboratory prototype into a reliable naval weapon proved extraordinarily difficult. A practical naval weapon would need to fire repeatedly with consistent accuracy, but maintaining acceptable barrel life became one of the program’s most difficult engineering problems. After investing roughly $500 million over more than 15 years, the Navy ended dedicated funding for its electromagnetic railgun program in 2021.