Even though observers have long speculated that Donald Trump and Elon Musk would eventually fall out, few predicted the speed and ferocity with which their social media beef erupted. Since Musk pledged his full-throated support for the president following an assassination attempt in Pennsylvania less than a year ago, the political and business interests of the two men have become increasingly intertwined. Musk claimed on Thursday that the president won the election because of him, and complained about "ingratitude". But could the bust-up with the White House prompt Musk not just to withdraw but throw his money behind opposition to Trump? Musk threatened to retaliate by decommissioning SpaceX's Dragon, which ferries astronauts and supplies to the International Space Station.