Calling unsafe libraries automatically makes the calling code unsafe by definition. You cannot have a 100% safe language that also interacts with its (unsafe) e

Calling unsafe libraries automatically makes the calling code unsafe by definition. You cannot have a 100% safe language that also interacts with its (unsafe) environment in any way. The language needs a way to express the lack of safety of an external library in order to clearly isolate it from the safe code sections. In Rust that's the unsafe block.