I do agree that the power of the media through electronics is way more powerful then atomic powers. I base my answer on this one comparison.
Atomic powers can create a massive form of destruction used at a given time. This destruction is devastating and is worthy of attention but ultimately it ends up being read about in history books.
As far as the media goes, it sends its form of destruction out everyday in ways that the general public will never completely comprehend. It weaves its way from country to country, state to state, and province to province. It makes its way any way we let it, touching every possible life it can until finally its destruction is widespread and nearly undiscernible. The history books will never record this because the electronic media endeavors to change the past history and form the history yet to come. The media will never be considered a history project because it is always continual. Therefore the electronic media powers are way more powerful than any atomic power any country can and will produce.