All of the grammar folks out there will recall certain rules about Subject-Verb agreement, and placement of "Ly" adverbs.

A condensed version is that "Ly" adverbs are placed between subject/verb in English sentences to describe actions the subject itself is taking via the verb used, and noun-descriptively when placed after a subject but not followed by a verb.

In other words, "posthumously" is out of place, here.

Correct grammar:
“…would let President Joe Biden promote Grant posthumously”.

👉 RealSGAnon
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