Once upon a time there was a Tumblr account called Nick Clegg Looking Sad, which consisted almost entirely of pictures of the then deputy prime minister looking miserable.

It doesn’t seem to have been updated since the 2015 general election, presumably because that represented peak misery, but I was reminded of it on Tuesday when Clegg made his first outing as spin doctor for Facebook. He had been given some happy news to impart, including the creation of a centre for electoral integrity to try to fight political disinformation campaigns aimed at skewing elections. But the pained expression crept in when confronted on TV with examples of the kind of graphic Instagram posts that 14-year-old Molly Russell’s bereaved parents believe had a bearing on their daughter’s suicide, and asked whether he would want his own children to see them. There is something horribly familiar about the sight of Clegg publicly squirming over the consequences of things he doesn’t quite have the power to stop, as if the coalition years were happening all over again in slow motion.

Former party leaders have to do something with the rest of their lives, obviously. Like Tony Blair and Gordon Brown before him, Clegg is far too young to retire, and it seems he has said all he wants to say about Brexit. A corporate gig does at least beat making expensive speeches to bankers or offering private advice to foreign governments with murky human rights records. But the sight of a former deputy prime minister spinning for Mark Zuckerberg feels nonetheless symbolic of everything that is wrong with the relationship between big tech and politics. Clegg used to help run the country, and now Facebook seems to be running him. Is that really the way it’s meant to work?

There has been a revolving door between Whitehall and Silicon Valley for many years now, with a steady stream of former special advisers being snapped up by the Googles and the Ubers and the Facebooks. It makes sense on one level – both politics and tech are bewilderingly fast-moving, complex environments with significant impact on ordinary lives and people who have worked in one are perhaps unusually suited to working in the other – but it also illustrates the problem. The single biggest threat to the seemingly unstoppable rise of the tech oligarchs would be a government with teeth, prepared either to regulate platforms more strictly or to tax them more heavily. These companies, like any company, will naturally seek to anticipate and where possible frustrate any political threat to their business model. The obvious way of doing that is hiring people with understanding of, and preferably influence over, the political process.

But the Facebook empire (which also includes Whatsapp and Instagram among other platforms) now has a broader reputational problem, too. Even if it could square off the politicians, its own users don’t like what they are hearing about everything from invasions of their personal privacy to the toxification of public debate and the role of social media in fuelling the rise of far-right movements. By hiring a politician rather than an anonymous former special adviser, Facebook seems to be trying to engage directly with the public.

It’s a risk for both sides. Politicians are used to articulating their own views, not parroting other people’s, and it may take Clegg a while to get used to answering questions about the limits of regulation in Zuckerberg’s voice rather than his own. But the bigger reputational risk is perhaps to Clegg personally, and, by association, the Liberal Democrats in general, whose members care more than most about questions of privacy, freedom of speech and civil liberties.

He has presumably gone in believing that Facebook really does want to be a force for good now; that it’s better to be in the room when the decisions are taken than outside railing hopelessly against them, and that whatever concessions he can extract are worth the awkward compromises that will sometimes need to be made. And yes, all that may sound a bit familiar to Liberal Democrats who lived through the coalition years. Let’s hope that’s not an omen.

• Gaby Hinsliff is a Guardian columnist