Interesting blog post from the WSJ yesterday:
http://blogs.wsj.com/speakeasy/2016/02/18/sample-five-heavy-metal-bands-from-around-the-world/

Here is the related article:
http://www.wsj.com/articles/the-weird-global-appeal-of-heavy-metal-1455819419?tesla=y

I don't find it "weird" that heavy metal music, attitude and culture have a global appeal today.
Metal is related to punk, but probably more widely acceptable because it is less overtly political.
Both deal with rage, alienation, injustice, the same theme of fighting a perceived "machine" that
goes back to Bartleby the Scrivener and back. There are many millions, perhaps billions, of people
in this world who feel alienated, disempowered to varying degrees and chaffed if not enraged by it.
Some music soothes the soul, some stokes the fires. Metal is more the latter.

-- Tom Fine