Did you look up the definition of civil officer of the United States? Obviously not!
An "
officer of the United States" is a functionary of the executive or judicial branches of the federal government of the
United States to whom is delegated some part of the country's sovereign power. The term "
officer of the United States" is not a title, but a term of classification for a certain type of official.
Officer of the United States - Wikipedia
In the case of Blount, Congress made the same mistake as you did. It is well documented.
Failure, followed closely by an epic failure by trying and failing to support your contention.
Consider yourself educated on this topic.