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I see 어떻길래 used often in news headlines. How would you translate this into English?

I would translate "어떻길래" as "For what reason," or "Because of what reason"

1. 어떻길래" is from a verb, 어떻다 = 어떠하다.
어떻다 (verb): To be what way, To be what reason (might sound funny in English)
어떻게 (adverb): With what way = How, With what reason = Why

Examples)
어떻게 가수가 될 수 있어요?: With what way can I become a singer? How can I become a singer?
어떻게 나한테 관심이 없나요?: With what reason is he not interested in me? Why is he not interested in me?

2. "~ 길래" means "For doing ~." or "because ~."

Examples)
These are direct translations, so they might sound awkward in English. Hope you will get the meaning of ~길래 though. (Native English Speakers: Please let me know if you can think of a better expression to translate these sentences in English).

뭐 하길래 전화를 안받아? [Because what you were doing], you are not answering the phone?
뭐가 그렇게 좋길래 노래를 부르니? [Because what makes you that happy], you're singing?
사랑이 뭐길래 나를 힘들게 하나? [Because what love is], it's making my life harder?

Therefore,
어떻다 (to be what reason) + ~길래 (because of): 어떻길래 (because of what reason)

Hope this makes sense.