|The U.S.A. is currently in the planning stages of designing a new SSBN and and accompanying SLBM to replace the Ohio/Trident II system in the 2020-2025 timeframe.
Simultaneously Russia, is working on its own new SSBN and so is China, while other countries such as India are likely to acquire them too.
So, how will this new generation (I believe it will be the 4th) of SSBNs and possibly nuclear SSGNs (or any other type of submarine that you can think off which could be used for strategic nuclear deterrence) differ from the current generation? The current SSBNs appear to be near perfection - what is there to improve upon? And last but not least, will the new generation be built in similar numbers as the current one, or will we see a reduction (or perhaps even an increase if the strategic situation changes)?