Here's why:
* Early Deaf Education: The first schools for the deaf in America were founded in the 1800s and used methods based on French Sign Language, which was the dominant sign language in Europe at the time.
* Isolation from spoken languages: The deaf community in America developed its own sign language, which evolved separately from spoken English.
* Visual and spatial elements: ASL is a visual language with its own grammar and structure, distinct from the grammatical structure of English.
While ASL borrowed some signs from LSF, it has developed its own unique vocabulary, grammar, and cultural context.
It's important to note that there are many sign languages around the world, each with its own history and development. They are not simply "translations" of spoken languages.