I'm waking up to ash and dust
The first way to take this line is that the narrator is literally describing the end of the world. This song came out the same year as December 21, 2012, where a lot of people were predicting the end of the world. And shortly after that came the North Korean nuclear threats. Both these events give some credibility to the idea that this line means exactly what it sounds like: the end of the civilized world.
But it seems more like the depressing landscape isn’t a prediction of what is going to happen — it is a description of what is going on right now. Sure, it isn’t like the whole world is literally a wasteland, but there are countless political and economic issues destroying the world we live in.
The whole “waking up” idea might have something to do with the rebirth of a phoenix. When a phoenix dies, it bursts into flames then is immediately reborn in the ashes. So the narrator could be comparing this awakening he has experienced to the rebirth of a phoenix.
Comments from the writer of the song Dan Reynolds steer the meaning away from an actual post-apocalyptic world, but the song can mean to you whatever you want.
“A lot of people probably see a post-apocalyptic world when they hear ‘Radioactive,’ understandably, but we wanted to deliver something that was maybe a little different from that … a lot different from that.”
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