However, most of Trump's time as POTUS was not under oath before a court, nor was his life prior or since being POTUS.
EXCERPT:
Abstract
Sections 1621 and 1623 of title 18, variously amended, of the U.S. Code define perjury before a Federal tribunal. The elements of perjury are (1) that the declarant took an oath to testify truthfully, (2) that he willfully made a false statement contrary to that oath (3) that the declarant believed the statement to be untrue, and (4) that the statement related to a material fact. It is easy to prove that a declarant took an oath. To prove that the witness gave a willfully false statement, however, the question asked must have been unambiguous. Moreover, the U.S. Supreme Court has ruled a perjury conviction cannot be based on merely unresponsive or evasive testimony calculated to mislead but containing the literal truth. Testimony is material if it can impede the proceeding or influence the decision of tribunal or investigating body and may pertain to the main issue, collateral issues, or even the credibility of witnesses. Section 1621 is violated once a declarant makes a false statement. However, Section 1623 establishes his right to recant previous false testimony. The recantation must be made in the same continuous court, the false statement must not have substantially affected the proceeding, and the falsity must not otherwise have been detected. The Declarant may then use his recantation to show an absence of intent to mislead. ...
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OJP is the federal government’s leading source of funding and research to strengthen the justice system, support law enforcement, and enhance victim services.
www.ojp.gov
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"We" would make any statement by any human be made under oath.
Reality is that such is near impossible and impracticable.
I'm sure you would flunk within five minutes. As would most all here. (You just did in the post of your's I'm quoting, IMO)