Silicon Valley-backed defense firms face growing pains after hot streak

US defense technology companies have roughly doubled their share of Pentagon contracts over the past year, but they face growing pains as they try to evolve from hot startups into heavyweights capable of building weapons at scale. Valuations for unlisted firms developing everything from unmanned “wingman” fighter jets, drone boats and AI-driven autonomous software have surged this year, alongside a rise in small Pentagon contracts, as the success of drones in Russia’s war on Ukraine has intensified interest in next-generation weapons.

For instance,…