Breaking up is hard to do, and even harder if you are a billionaire who decides to break up with another billionaire on the two social media platforms you own, while the world watches in real time. Here are the key moments as the relationship between the US president, Donald Trump, and his former senior adviser Elon Musk unravelled in spectacular fashion, precipitated by a dispute over a colossal spending bill that could have major consequences for years to come.
