Chief Justice Robert's Messing the Oath

Most of the talking heads when commenting about the Chief Justice Roberts’s verbal stumble while administering the Presidential oath, focus on the adverb “faithfully.” Adverbs can be placed almost anywhere in the sentence and in most cases will not change the meaning.

On the other hand, not one of the pundits I've seen have talked about Robert's changing of “of” to “to” in the phrase 'President of the United States'. That slip is a much bigger deal. It changes the meaning and diminishes the Presidency.

Here's the way the Constitution says it should be administered:

"I do solemnly swear (or affirm) that I will faithfully execute the office of President of the United States, and will to the best of my ability, preserve, protect and defend the Constitution of the United States."

But this is the transcript:

ROBERTS: I, Barack Hussein Obama...
OBAMA: I, Barack...
ROBERTS: ... do solemnly swear...
OBAMA: I, Barack Hussein Obama, do solemnly swear...
ROBERTS: ... that I will execute the office of president to the United States faithfully...
OBAMA: ... that I will execute...
ROBERTS: ... faithfully the office of president of the United States...
OBAMA: ... the office of president of the United States faithfully...
ROBERTS: ... and will to the best of my ability...
OBAMA: ... and will to the best of my ability...
ROBERTS: ... preserve, protect and defend the Constitution of the United States.
OBAMA: ... preserve, protect and defend the Constitution of the United States.
ROBERTS: So help you God?
OBAMA: So help me God.
ROBERTS: Congratulations, Mr. President.

The phrase President of the United States is not open to variation. In what context would we ever say “President to the United States?”

One can speak of “an ambassador to the United States” or “an ambassador of the United States.”

In the first instance, to makes it clear that the ambassador belongs somewhere else. He may be attached to the United States, but it’s as an outsider.

In the second instance, the of makes it clear that the ambassador is carrying on the work of the United States.

So why would Chief Justice Roberts come up with the unprecedented “President to the United States” while delivering the oath of office?

Freudian slip maybe?