Hoarse Vance is deployed to make sure nothing is lost in translation with Iran
You can always tell when the White House knows it has a problem, when its allies are turning against it, and it has an awkward proposition to sell: It sends out the vice president.

TL;DR
- Vice president is sent out when the White House has a problem or unpopular proposition.
- JD Vance appeared in the briefing room with a seemingly hopeful demeanor.
- Marco Rubio and Karoline Leavitt were reportedly unavailable.
- The administration is attempting to manage the narrative regarding Middle East geopolitics.