The title isn't much help. I can't find a song called ONLY KIDS or THEY'RE ONLY KIDS—and there are LOTS of songs just called KIDS. I don't get any hits on Google using the quoted lines. I'm refreshing this thread in the hope someone will recognize it.

And by the way, once we have identified the song, I think it would be appropriate for some JoeClone to change the title of this thread to include the song title.

By the way, there are several clues this song is not American.