It is a same thing as happens in coaxial cables. Just imagine that Earth and its ionosphere is a kind of spherical coaxial cable. Or, say, it is a short piece of coaxial cable with cut ends shielded.

Theoretically, if you send RF energy into coaxial cable, it mirroring from inner core and shield and pass through with minimum losses. Same with Earth - if you send electromagnetic waves that fit that Earth-sized coax in one place, they could be gathered with little losses in any place on Earth with apropriate receiver.

However, the real thing could be much more complex to achieve, and with completely unknown side effects from radiating RF power sufficient for something useful into the gap between Earth and ionosphere. HAARP could look like a child toy in comparison.

So, even if Tesla's idea was definitely brilliant, that does not mean it really deserve to be implemented.

It is a same thing as happens in coaxial cables. Just imagine that Earth and its ionosphere is a kind of spherical coaxial cable. Or, say, it is a short piece of coaxial cable with cut ends shielded.

Theoretically, if you send RF energy into coaxial cable, it mirroring from inner core and shield and pass through with minimum losses. Same with Earth - if you send electromagnetic waves that fit that Earth-sized coax in one place, they could be gathered with little losses in any place on Earth with apropriate receiver.

However, the real thing could be much more complex to achieve with completely unknown side effects from radiating RF power sufficient for something useful into the gap between Earth and ionosphere. HAARP could look like a child toy in comparison.

So, even if Tesla's idea was definitely brilliant, that does not mean it really deserve to be implemented.