Why can't French people say the "h" sound?

Apparently, the sound does not exist in their language? Why is this so? What the hell kind of language doesn't have the "h" sound? It's the sound that humans make when they inhale and exhale. They make that sound when they laugh. It's intrinsic to the human species, so how can anybody not be able to make that sound? Why do they say 'ockey and 'amburger?