he has declared that free speech is the bedrock of a functioning democracy . what that means for twitter s 300 million users is not certain, as our technology editor zoe kleinman explains. lift off! elon musk s big ideas include colonising mars and implantable human brain machines. his successes include the tesla electric car and the payment giant paypal. and now he s set his sights on his favourite social network, twitter. this is not a way to sort of make money. having a public platform that is maximally trusted and broadly inclusive is extremely important to the future of civilisation. he wants to see less moderation. some people are delighted, especially those whose tweets have got them banned from the platform in the past, like the right wing commentator tucker carlson, who is now back.