I angered the Brotherhood of Steel by taking out a neutral squad (wanted to clap the legendary guy). Now wherever I go, they seem to remember it and try kill me. Can I resolve that without loading an old save?

I didn't do anything for them now, not even the "Fire Support" quest.

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2 Answers

As user fja3omega hinted at, and per this Reddit thread:

If you go far away from [the disgruntled], then wait in a chair (or whatever) for like 3 or 4 in game days they will get over it and not be hostile (this works with everyone).

Subsequent comments in the linked thread suggest it works.

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I personally think you screwed your opportunity to do the quests. Did you save before or have you already gone a bit to far from your save. Anyway the Brotherhood squads aren’t very hard to kill. Plus now you can join the institute without any problems. I joined it and became hostile toward the brotherhood. What about if you go on the Prydwen? I remember someone saying that if you kill a unamed soldier in the borherhood, the important people won’t become hostile.

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