i think /c/politics@lemmy.ml was removed due to redundancy with /c/worldnews@lemmy.ml more than /c/usa@lemmy.ml.

that’s not to say it couldn’t be a place for non-news-related political discussions, but in practice it mostly got posts which would fit in worldnews.

it could be restored if one or more users with a good history wants to take responsibility for moderating it.