Will Oval Office be big enough?

MUSK AND TRUMP: CHANCES OF FRICTION HIGH - EXPERT

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Donald Trump will be the one taking the presidential oath next week, but in some respects, billionaire Elon Musk might as well place his hand on the Bible, too.

In an unprecedented relationship for modern US history, Trump will be heading into the White House shadowed by an advisor who is the world's richest person and matches the incoming president in wild ambition, hard-right politics, and media influence.

Will the Oval Office be big enough for two outsized personalities, let alone the mountain of conflicts of interest trailing Musk? It's a political marriage sealed by Musk's bank-rolling of Trump's third tilt at the US presidency.

Lorenzo Castellani, a history professor at Rome's Luiss Guido Carli, warns "the chances of friction in the long run are high".