I said on Question Time that the failure to establish a Palestinian state living alongside a secure Israel was the greatest diplomatic failure in forty years. I feel that as a matter of security and justice - for both peoples. The drama in New York - public and private - this week will reflect that failure, and the mistrust it has engendered.

My view is that the use of the UN is a smart tactical move by the Palestinians. My reasoning is that nothing else has produced any give in the situation. In fact there is no peace 'process' to speak of. Equally, however, tactics are not the same as strategy. So the Palestinian side need to ensure that this move is not an end in itself, but a jump start to internationally backed - and timetabled - negotiations. President Obama's domestic fix on the issue is a real constraint, but I see real danger in the argument that nothing can happen until the US electoral timetable works itself through (see my Times article here (£)).

We do not know exactly what the end game, in terms of what a resolution might say and how it will be tabled, will be. But President Obama said at the UN last year that he wanted to see a Palestinian state take its place - in the midst of the Arab Spring this is a peaceful way to keep the political aspirations of the Palestinian people up the news agenda, when the Arab Spring could easily have left them marginalised. The appeal to the UN widens international engagement in a problem that has big international repercussions, but in which there is remarkably limited international engagement, and it firmly established President Abbas as the man making the big moves, not Hamas.

So there should not be a shock-horror reaction to political entrepreneurship from the Palestinians. One reason for that concerns a bit of history that I have not seen mentioned in any of the discussion of the events in New York: that concerns the 2002 Road Map that is notionally still being followed, and which avowedly sets out the notion of a state with provisional borders as a legitimate and transitional stage to the establishment of a fully fledged Palestinian state.

The Road Map was a Bush-Sharon creation. That will not inspire confidence in some quarters. But it is relevant here. It committed in Phase II to: "creating an independent Palestinian state with provisional borders and attributes of sovereignty, based on the new constitution, as a way station to a permanent status settlement. As has been noted, this goal can be achieved when the Palestinian people have a leadership acting decisively against terror, willing and able to build a practicing democracy based on tolerance and liberty. With such a leadership, reformed civil institutions and security structures, the Palestinians will have the active support of the Quartet and the broader international community in establishing an independent, viable, state."

Much has happened since then, including the splitting of Palestine between West Bank and Gaza. But in the West Bank the Abbas/Fayyad leadership has made strides on security recognised by the Israelis as well as independent players. (It is worth noting that we, outsiders, all agree that boosting Abbas/Fayyad should be a part of any approach). Critically, the idea of establishing a state before negotiations had been completed was considered sensible as a way of building confidence. The triggers for Phase II included a role for the Quartet, so the parallels are not exact, but the basic point holds.

That is why a creative Israeli reaction to Palestinian moves would have been to recognise the dangers inherent in its current and growing isolation - significantly the product of a mounting sense that her government is never going to be able to negotiate its way to a solution. In fact it was a senior Israeli leader - well before the current fracas - who first alerted me to the potential significance of the Road Map's provisions.

President Abbas has accepted that in and of itself a New York motion doesn't change things on the ground. So I would like to see three things as follow up. First, recognition that peace must be regional not just bilateral; the Arab states need to be part of this process, for example through the more formal role for an Arab Quartet that I have discussed before. Second, greater international engagement in the establishment of a formal and timetabled process. Third, continued serious state building efforts on economy, governance and security. Israel is rightly concerned about issues of security, and the hate propaganda that sometimes emerges in Arab and Palestinian media. Talks are the way to get those issues on the agenda.

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