For the benefit of people who read only the headline and not the article:
The story here is that the US government captured Russia's energy weapon, which Russia has been using against US personnel for a decade, and tested it to determine what it does (it causes brain damage). This story does _not_ claim that the US has developed a weapon like this themselves.
The effects aren't too far off from reports of the maduro raid, though my understanding is that the US just used a standard LRAD
It does claim the US went to great lengths to dismiss the victims for a decade, while being in possession of the device. That raises the question of what incentives the US would have to deny its existence. To me, that was the story.