The best answer is an explanation in their own words, the French whitepaper on defense and national security: https://media.nti.org/pdfs/15-Fr.pdf https://media

The best answer is an explanation in their own words, the French whitepaper on defense and national security: https://media.nti.org/pdfs/15-Fr.pdf https://media.nti.org/pdfs/15-Fr.pdf . "Nuclear attack submarines carrying cruise missiles are a priority. Due to their stealth and virtually unlimited range, they represent versatile strategic systems that can be used for intelligence, protection of the nuclear submarines [here they are referring to their ballistic missile submarines], escort of the aircraft carrier or special operations. The White Paper sets a target of six submarines." In addition, they can be used on their own to launch strikes against high value targets (things like the chemical weapons facilities in Syria). They are also very useful in the Indo-Pacific to deter China (France still has territorial possessions in southeast Asia): https://warontherocks.com/2021/04/how-franco-australian-cooperation-can-help-stabilize-the-indo-pacific/ https://warontherocks.com/2021/04/how-franco-australian-coop... .