hi, eslbro. in the english language, the word "jew" is what is called a "proper noun"; which is a noun that refers to a specific person, thing, or place. in this case, the thing in question is the specific group of individuals known as "jews"--individuals that follow the specific religion of judaism. proper nouns are always capitalized in english, so it's the same for "buddhists", "christians", "muslims", "hindus", etc. hope that helps.
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