california is ~160,000mi^2 and france is ~244,000mi^2 (423 megameters squared, 632 megameters squared, metric), the population density, respectively, is 251/mi^2 and 281/mi^2. You're comparing an entire country to a single state (2% of the US states, in fact.)

I like to point stuff like this out whenever someone compares an entire EU country to some US state.

note: i edited the france density, as i did accidentally transcribe the wrong value. France is slightly denser per sqkm.