Дело в том, что местоимение we иногда может употребляться в английском языке в некорректной форме, в данном случае us.

Usage Note: Appositive nouns or noun phrases sometimes lead writers and speakers to choose incorrect pronoun forms. Thus us is frequently found in constructions such as Us owners will have something to say about the contract, where we is required as the subject of the sentence. Less frequently, we is substituted in positions where us should be used, as in For we students, it's a no-win situation. In all cases, the function of the pronoun within the sentence should determine its form, whether or not it is followed by a noun or noun phrase. See Usage Notes at be, I1.

https://www.thefreedictionary.com/we

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Note added at 45 мин (2019-10-28 16:51:41 GMT)
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или можно сказать:
выработать менталитет коллективного «я»