The cost to design one is insanely expensive, the advantage of the U.S. designs is they have a very long operating history with a bunch of subs so all those lessons learned from 70 years of operation are factored into the designs and the U.S. buys a bunch at once which lowers the cost per unit and makes keeping maintenance facilities available for the subs much cheaper as well.
The U.S. has 66 active nuclear subs, the UK has 10 and France 9 so again while it’s possible to do it would be very expensive
The cost to design one is insanely expensive, the advantage of the U.S. designs is they have a very long operating history with a bunch of subs so all those lessons learned from 70 years of operation are factored into the designs and the U.S. buys a bunch at once which lowers the cost per unit and makes keeping maintenance facilities available for the subs much cheaper as well.
The U.S. has 66 active nuclear subs, the UK has 10 and France 9 so again while it’s possible to do it would be very expensive