What is the main barrier to building modern destroyers, frigates, and cruisers?
Short answerThere is no single universal barrier; shipyard capacity, industrial investment, skilled labor, funding, and naval recruitment interact differently in each country.
NotesThe main constraint depends on the country and whether its yards and suppliers have received sustained investment. Recruitment and the loss of infrastructure during the post-Cold War peace dividend also limit Western shipbuilding. Even with adequate funding across the system, radars, sonars, computers, and combat-system software can hold up completion. Building a hull quickly does not ensure that the military electronics needed to fit it out will arrive at the same pace. Commissioning dates can therefore conceal differences in how ready a ship is to operate.