They didn’t just build an aircraft carrier, they built a nuclear powered CATOBAR carrier. In terms how rare that is; the US and France are thus far the only nations to have ever done that. Maybe in the future , China will join that exclusive club, with their projected type 4 carrier.
The somehow bizarre idea coupled to this, is that somehow France does not have a navy. Excuse me?

Aircraft carrier Charles De Gaulle and Horizon-class air defence destroyer Chevalier Paul during underway replenishment with the support ship Jacques Chevallier.
The French Navy is one of the world’s most advanced navies, mustering 180 ships, including a nuclear powered aircraft carrier, several air defence destroyer easily on par with the latest versions of the Burke-class destroyers, Mistral class Amphibious assault ships, Suffren class nuclear powered attack submarines, Triomphant class nuclear ballistic missile submarines, FREMM-class frigates (that were chosen as the basis for the new USN Constellation class)
In fact the French Navy introduced a new frigate in 1996, and since then all newly designed surface warships have incorporated their clean lines. This was the first “stealth” frigate La Fayette.

La Fayette-class frigate FS Courbet
In short the French Navy is one of the largest (by tonnage) and most capable navies in the world, with some unique capabilities, that only the mighty US Navy can top.