HAARP Question

I have a simple question for believers that HAARP can affect weather worldwide:

Supposedly it warms the ionosphere with electromagnetic radiation. By definition this radiation travels in a straight line, therefore couldn't go beyond the horizon of its Alaska location. Theoretically, it could affect the jet stream, but this would be highly inaccurate and take days to propagate to locations far away...

How is this problem explained?

surely the essence of radiation, is to radiate outward 360 degrees, i'm still looking into it all, so i'm gonna be keeping a lookout on what is said thanx to your question.