I agree about the security issues.
As for the technology, I don't see why they should have any problems - Rolls-Royce have been designing and building small pressurised water nuclear reactors for British submarines since 1965, and still do so today. A new reactor built by RR, but ironically a new US design based on RR technology, will power the new Dreadnought class submarines, currently under construction.
That's why I could never understand the rush to hand design, build and operation of nuclear power stations to foreign companies (and governments), after a long history of nuclear reactor design and development in this country. Hopefully, our withdrawal from Euratom will not mean that we no longer play an active role in the Generation IV International Forum (GIF) too.