Ben Kentish, President of the Cambridge Union Society, explains why Marine Le Pen was invited to talk on Tuesday 19 February

Marine Le Pen's talk at the Cambridge Union last week unsurprisingly divided opinion. There was a protest by Unite Against Fascism and one of the NUS campaign groups, and criticism from several other groups. However, 'courting controversy' is far from the reason for the union inviting such speakers, and I am convinced that the decision to host Mme. Le Pen this week was the right one. In a Comment is Free piece last week, fellow Cambridge student Conrad Landin's asked why Le Pen was invited. I am happy to explain why.

For nearly 200 years the Cambridge Union has existed to promote free speech. At times this inevitably leads to controversy. In the 1960s, it stemmed from the Union's invitation to Enoch Powell and Oswald Mosley. Last term it was Julian Assange, and before that Dominique Strauss-Kahn. This time it was Mme. Le Pen.

The fundamental reason behind all of those invitations is a belief that freedom of speech is universal, and cannot simply be withdrawn from those whose views we may not like. The free exchange of views and ideas is the bedrock of our society, and that is threatened when it is restricted. Some in recent days have argued that it is also threatened by 'fascism'. This may be true, but the answer is surely not to fight 'fascism' with its own prescriptions.

Instead, the response to disagreement in any modern society must be open debate. To attempt to silence one's opponents and pretend their views will simply go away makes no sense. That applies all the more if you believe those opponents are against the concept of free speech. The only adequate response to that is to promote free speech even further, and defend it even more strongly.

The free speech argument, however, is only part of the story. The union also exists to promote the open and frank exchange of ideas. That ideal is the fundamental basis of democracy, but becomes entirely redundant if the only ideas exchanged are those that the majority already agree with. Soon after the announcement of Mme. Le Pen's visit, someone emailed me a quote about free speech needing to protect unpopular speech, as popular speech by definition needs no protection. I could not have put it better myself. In a society where debate too often becomes a competition of who can shout the loudest, and political debate is condensed into soundbites, the genuine discussion of ideas - all ideas - is something valuable that needs protecting.

In fact, in this regard the term 'no platform' is unhelpful. It suggests a stage on which the speaker is free to spout their views without challenge. This could not be further from what the Cambridge Union is about. Free speech at the union works both ways; the speaker is free to express their views, but members are equally free to challenge them on what they say - and challenge they certainly did. Mme. Le Pen was asked numerous questions, criticised by audience members for her views on issues such as immigration and radical Islam, and asked to explain comments attributed to her father.

In fact, given Mme. Le Pen's appearance on BBC's Newsnight earlier this month, it seems surprising that yesterday's event caused such a stir. That interview provided her with a 'platform' to hundreds of thousands of British households, with viewers offered no opportunity to engage with or challenge her views. This caused little reaction and seems significantly less controversial than her visit to the union, during which the audience were free - and did - directly criticise and question her beliefs. Seemingly people realise that an appearance on Newsnight is not an endorsement from the BBC. In the same vein, nor is an invitation from the Cambridge Union, which doesn't make value judgements about the speakers it invites.

It is easy to portray the idea of 'No Platform', as Mr Landin did, as something reserved only for the most extreme of speakers. This does not prove true when the facts are considered. Last year a group of Cambridge students successfully prevented David Willetts from delivering a lecture. They took away his right to speak, and the right of students here to challenge him. Why? Because they didn't like what he had to say. While that event was met with widespread condemnation from fellow students, it was not a one-off. In the last two years protestors have also attempted to silence Eric Pickles and Jeremy Hunt during their speeches at the Union, for the sole reason that they didn't agree with them. The NUS also has a 'No Platform' policy against George Galloway and Tony Benn. 'No Platform' has become a tactic to silence those that some groups disagree with.

Indeed, the sad irony was not lost on many that it while union members directly criticised and challenged Le Pen on her views, the 'anti-fascist' protestors outside were the ones physically attacking someone because of her beliefs (a mob tried, unsuccessfully to assault Le Pen on her entry to the building), repeatedly trying to force entry to a building, and making death threats to students and security staff.

Last year around 75% of Cambridge freshers made the decision to join the union. They did so to hear interesting and influential speakers, and to have the opportunity to challenge those speakers on what they say. When the current union building was opened in 1866, Lord Houghton stated his desire that the society would, in the coming years, continue to "tolerate even the intolerable". In defence of universal free speech and the open debate of ideas, that is what it continues to do today.

Follow The Cambridge Union Society on Twitter: www.twitter.com/cambridgeunion