Using define directive to get the namespace name

Having such a simple C++ code:

#include <iostream>

#define NS NS_Static
#define MAKESTRING(x) #x

namespace NS {
  int global_x = 8;
  void print_global_x() {
    std::cout << MAKESTRING(NS) << "::global_x: " << global_x << std::endl;
  }
}

I'h expected to get on output NS_Static::global_x: 8 BUT getting just NS::global_x: 8. I've asked a similar question earlier and the user Eljay provided me an answer to use such an extra code:

#define NS Static
#define MAKESTRING_HELPER(x) #x
#define MAKESTRING(x) MAKESTRING_HELPER(x)

It finally works but can someone please explain my why my original approach doesn't work?