They’re the Washington couple at the center of power in the Trump administration. They’re also straddling opposing sides of an explosive breakup between President Donald Trump and billionaire Elon Musk.

It began with Musk complaining about the centerpiece of Trump’s legislative agenda, which the president at first took in stride. Eventually Trump let slip that he was disappointed in his former adviser, prompting Musk to unleash a flood of insults and taunts.