Twitter has taken both a huge and a tiny step in deciding to tag President Trump’s tweets about postal voting in California with a link to a fact-checking page. It is huge because this is the first time that any social media platform has even come close to censoring the President when he makes false statements and because it appears to go against Twitter’s own ‘free speech for politicians’ policy.

But it is also tiny because it is merely a link to another page, a tag applied many hours after the original tweets. And as the Guardian and others have shown, the link doesn’t appear in some cases if you reproduce the tweet elsewhere.

That Twitter should choose to make this decision for posts about elections is not that surprising. The company has singled out attempts at “manipulating or interfering in elections or other civic processes” for special attention. That said, the platform failed to act when President Trump made false statements claiming that Michigan would be sending a ballot to every voter by mail (they are merely sending a postal vote application – something done by many Republican states). It might be cynical to look at the company taking action when the tweets are about their home state of California as being significant, but there you are.

The tweets in question are a repetition of the sort of thing the President said in the Michigan case – that the state would be sending ballot papers to anyone living in the state, even if they are illegal immigrants (that bit is implied) and that state officials would then tell people how to vote. Each aspect is clearly false. The linked fact checking page is pretty good – it aggregates a range of journalists and others explaining why the President’s statements are not correct. How many of the President’s followers will actually read it remains to be seen however.

Predictably, the President is claiming that this action has infringed his right to free speech, and that he ‘will not allow it to happen’ despite platforms having the right under federal law to decide how to moderate what appears. His campaign manager Brad Parscale claimed that this justified his decision to end Trump’s advertising on Twitter, despite the platform itself taking the decision to end all political advertising in 2019, something the Trump campaign at the time complained was biased.

My own view is that I do not believe that Twitter would have taken this decision if it were to be a one-off. They will be generating a huge backlash which will only be justified if they really intend to push on and have a similar form of fact-checking for future statements by Trump and other candidates. Whether they will limit their actions to tweets about elections or spread the net further will be closely watched. In the meantime, it is also a shot across the bows for Facebook which has refused to allow its third-party fact-checkers to critique the posts of politicians and other world leaders.