I'm only a rust noob but I'll take stab at this:
Looks a lot like C to me. I'm told it has some features that look like they came from Haskell, Ruby and so on.
I have used Ada a bit years ago, in a secure wireless communication system as it happens, I don't recall anything in Ada referred to as "the security portion". Please clarify what you mean.
Rust is statically and strongly typed. Like Ada.
Locals, yes. I'll let others comment on globals. Strongly discouraged.
Nothing will guarantee the "security" of your program if you mean "security" as is typically meant by a computer security researchers and penetration testers.
Rust does however guarantee memory safety and data race safety by not allowing multiple references to the same data that allow it's mutation and not allowing data to be read whist it is being mutated. These rules are checked and enforced at compile time and so incur no run time performance cost.
By the way, Ada is looking into adopting something of the Rust anti-aliasing features now.
I think one of the best explanations of that "magic souce" is in this presentation:
"Polonius: Either Borrower or Lender Be, but Responsibly - Niko Matsakis": https://www.youtube.com/watch?v=_agDeiWek8w&t=4s
For the best practical introduction to data lifetimes and the borrow checker see here:
"Crust of Rust: Lifetime Annotations": https://www.youtube.com/watch?v=rAl-9HwD858
Rust is fast because it compiles to native code, like C and C++ do. Like them it also has no garbage collector or run time to slow things down. Rust uses LLVM to generate and optimize code, as used by clang, so performance is comparable.
Why Rust of course. The front end anyway. The back end leverages LLVM.