The Islamic Movement cleric Raed Salah won his appeal this week against a decision by the Home Secretary to exclude him from the UK. The judgement is a sign of our weakness and confusion in the face of extremism.

The Israeli newspaper of record, Ha'aretz, reported that Salah was first charged with inciting anti-Jewish racism and violence in January 2008.

The head of the Islamic Movement in Israel's Northern Branch, Raed Salah, was charged on Tuesday in Jerusalem Magistrate's Court with incitement to violence and racism over a fiery speech he gave a year ago in which he invoked the blood libel.

During the speech at the 16 February, 2007 protest in the East Jerusalem neighbourhood of Wadi Joz, Salah accused Jews of using children's blood to bake bread. "We have never allowed ourselves to knead [the dough for] the bread that breaks the fast in the holy month of Ramadan with children's blood", he said. "Whoever wants a more thorough explanation, let him ask what used to happen to some children in Europe, whose blood was mixed in with the dough of the holy bread."

This week - and this has not been sufficiently noted - the Appeal Court decided that Salah had invoked the antisemitic blood libel: "We do not find this comment could be taken to be anything other than a reference to the blood libel against Jews." It also decided that this would 'offend and distress Israeli Jews and the wider Jewish community." As for Salah's tangled efforts to explain away his speech, the judgement was scathing:

If he had meant to refer to Christians using the blood of others to make bread, which he seems to consider less offensive than referring to Jews doing so, then he could have inserted the word 'Christian' into the text of his sermon as he does in paragraph 175 of his explanation. Allusion to historical examples of children being killed in religious conflict does not require reference to their blood being used to make 'holy bread'. The truth of the matter is that the conjunction of the concepts of 'children's blood' and 'holy bread' is bound to be seen as a reference to the blood libel unless it is immediately and comprehensively explained to be something else altogether.

A suitable way was found to warn the 4,000 Jews who work every day at the Twin Towers to be absent from their work on September 11, 2001, and this is really what happened! Were 4,000 Jewish clerks absent [from their jobs] by chance, or was there another reason? At the same time, no such warning reached the 2,000 Muslims who worked every day in the Twin Towers, and therefore there were hundreds of Muslim victims.

And yet, despite all this, the Court upheld Salah's appeal.

Following the judgement there has been an effort by Islamists and the far left to demonise Israel's friends in the UK and to poison relations between them and the UK government. At a press conference that was swiftly organised by the pro-Islamist group Middle East Monitor (MEMO), Raed Salah's lawyer Tayab Ali targeted "pro-Israel lobbying groups" alleging they were "able to directly influence government policy."

Also at the MEMO press conference was the left-wing Labour MP Jeremy Corbyn. About Salah, Corbyn has said 'He is far from a dangerous man. He is a very honoured citizen, he represents his people extremely well, and his is a voice that must be heard.' Corbyn added, 'I look forward to giving you tea on the terrace because you deserve it!' Backing the call for a public enquiry into the influence of 'pro-Israel' groups and individuals on the government, Corbyn claimed this went 'to the heart of what's going on in the Home Office and the way the government makes decisions.'

UK political culture is changing. On its margins it now has a place for those who foment tension and radicalism. They can be hoisted into Parliament as 'socialists.' They can be promoted by serious and once venerable liberal newspapers. And now, it seems, they are to be taken for tea on the terrace.