I found this sentence in [an article about japanese swords](https://newsinslowjapanese.com/2020/03/24/nisj-354-japanese-swords/)

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> 日本刀と他の刀との違いは、どれだけ波紋と鉄が美しい**か**にこだわっている**か**です
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The translation is

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> The difference between japanese swords and other swords **is** how much the ripples and iron are particular to their beauty
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But since か is used to carry a sense of questioning shouldn't it be more like

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> The difference between japanese swords and other swords **could be** how much the ripples and iron are particular to their beauty
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Any help on how to parse and understand どれだけ波紋と鉄が美しいかにこだわっているかです would be appreciated :)
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The basic structure of this sentence is:

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> 日本刀と他の刀との違いはX**です**。  
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> The difference between Japanese swords and other swords **is** (in) X.
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The "is" in the translation simply corresponds to the copula です at the end of the original sentence. There is no need to change it to something else like "could be".

The "X" part consists of two nested [embedded questions](https://japanese.stackexchange.com/a/13038/5010):

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> 【どれだけ【刃文と鉄が美しい**か**】にこだわっている**か**】  
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> 【how much [blacksmiths] are particular about 【whether their [*hamon*](https://en.wikipedia.org/wiki/Hamon_(swordsmithing)) and iron are beautiful】】
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(I believe 波紋 is a misspelling and thus "ripple" is a mistranslation. The correct kanji is [刃文](https://ja.wikipedia.org/wiki/%E5%88%83%E6%96%87). That said, this misspelling is understandable because 刃文 has a wavy appearance.)
I would parse it this way:

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> The difference between Japanese swords and other swords is this: How much do they care about "how beautiful are the ripples and iron?"?
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And since this way there are essentially two implicit questions in this phrase it makes sense that there are two か.