If the TUC adopts the resolution proposed by the Fire Brigades Union, the implications are far-reaching.
First and most important, it opens the way for the Labour Party, in which the unions play an increasingly important role, to shift its own views on the Middle East toward a more pro-Palestinian position.
This could result in the British government supporting sanctions targeting Israel. As the UK is a permanent member of the UN Security Council, this might even mean an eventual push for UN sanctions against the Jewish state.
At the moment this might be dismissed as irrelevant, for Labour is not expected to remain in power beyond next year.
But the idea that one of the two main political parties in Britain would support sanctions against Israel is a dangerous precedent.
It also means that individual British unions, which may at one time have promoted a two-state solution and invited Israeli trade unionists to their conferences, may stop doing so. Unison, for example, is already retreating from its traditionally even-handed approach, and no longer invites Histadrut (Israel’s national trade union) to its conferences.
The other effect will be within the international trade union movement.
At the moment, Histadrut is a member of both the International Trade Union Confederation and a number of the global union federations (GUFs) which are organised by sector. (The recent expulsion of the Israeli journalists’ union from one of the GUFs was exceptional.)
While there are some trade union movements that are openly hostile to Israel (such as Cosatu in South Africa), others (most notably unions in the USA and Germany) remain sympathetic.
Were the TUC to sever its relationship with Histadrut, as the resolution proposes, this could trigger a major fight in the international trade union movement. All this might come to a head at the international trade union congress due to be held in Vancouver in June 2010.
Unions with strong ties to the Histadrut are likely to put up a fight and this could result in the first split in the global trade union movement since the Cold War.