Elon Musk has been a constant companion to President-elect Donald Trump as Trump meets with foreign leaders — an ever-present personality at Mar-a-Lago since November, even accompanying Trump to Paris on his first foreign trip since winning the election.  

Musk’s proximity to the incoming president has given him invaluable access to heads of state, including French President Emmanuel Macron at the ceremonial reopening of Notre Dame and Italian Prime Minister Giorgia Meloni in New York,…