Richard Goldstone's partial recantation over his report into Operation Cast Lead in Gaza should be a defining moment in the relationship between the British political class and Israel.
The judge's withdrawal of his claim that the IDF targeted civilians removes one of the central arguments for describing those who ordered the attacks as war criminals.
The fact that the Israelis are carrying out their own investigations into 400 instances of alleged abuse also undermines the case for referring the matter to an international legal body.
Writing in the Washington Post, Mr Goldstone recognises the Islamist government in Gaza now has a far more serious case to answer.
So will the demonstrations outside every event at which an Israeli politician or diplomat speaks now stop? Will people start to picket events where the UK's legion of apologists for Hamas speak?
I somehow doubt it. Those particular battle lines were drawn a long time ago. I don't hear many calls for Hamas war criminal to be hauled to the International Criminal Court in the light of Richard Goldstone's remarks.
However, it should be possible to shift the debate within parliament itself. This is not to say those 400 allegations of abuse should go unremarked or that Israel can avoid being held to account for the events of winter 2008/9.
Mr Goldstone remains convinced that the Israeli investigations are taking too long and bemoans the fact that the authorities refused to cooperate with his investigations.
The Goldstone Report stood as a terrible stain on Israel's reputation and represented a direct challenge to parliamentarians who chose to describe themselves as Friends of Israel.
How could a country that targeted civilians continue to describe itself as the only democracy in the Middle East?
The Arab Spring nailed the lie that the anger of the "Arab Street" was fuelled by the Israel-Palestine conflict. Richard Goldstone's breathtaking retraction should shift the debate still further.
On a practical level, it will make the argument for reform of the law on universal jurisdiction easier as the Policing and Social Responsibility Bill passes through its latter stages. The original Goldstone report provided the argument for those who would make Israel a pariah state.
With that argument removed, it would be fanciful to expect the international community to embrace Israel with open arms.
But is it too much to expect the debate on Israel in the UK to become a little less hysterical?