The late Conor Cruise O'Brien used to refer to the sense of liberation he felt once he was no longer involved in party politics. It enabled him express his views freely without being bound by any collective responsibility. On the issues that interested him, such as Northern Ireland and the Middle East conflict, his views were at odds with the political mainstream. As a party politician he was fettered by the need to express the predictable well-meaning banalities that are expected on such topics. As a writer free of party ties he was free to follow the logic of his own arguments even if his views caused offence.
Jenny Tonge is hardly a thinker in O'Brien's class (and he had rather different views on Israel), but similar considerations apply. The Israel/Palestine conflict is an issue on which mainstream politicians in the West watch their words and strive for balance because what they say reflects more widely on their party and even on their country. It is hard to combine holding public office as a respresentative of a political party with expressing controversial opinions on issues like this. So Baroness Tonge has had to choose between resigning the Lib Dem whip or apologising for comments which the party leadership found embarrassing and offensive.
Tonge's defenders will doubtless say that there is nothing terribly controversial about saying Israel won't 'last forever' because it is true of any political entity. But this won't quite do. In such matters context is all important. If a well-known politician were to say with reference to Scotland becoming independent that the United Kingdom may not last in its present form then it would be relatively uncontroversial. Every expectation is that if such an eventuality arises it will happen peacefully and by mutual consent. If they made a similar comment with regard to Northern Ireland, with its recent history of politial violence, it would immediately raise the spectre of a United Ireland and the hackles of the Ulster Unionists. In the case of Israel, the existence of which has been controversial from its inception, saying it will not last forever is clearly going to be read as a thinly-veiled threat.
A similar point can be made about Tonge's previous faux pas in saying that had she lived in Occupied Palestine she might have considered becoming a suicide bomber. At one level this is such a statement of the bleeding obvious as to be hardly worth saying. Similarly had I grown up in one of the world's major conflict zones rather than in Watford I might not have arrived at the warm cuddly Liberal opinions that I hold. Who knows what any of us might do if we lived somewhere that was beset by persistent violent conflict. So the purpose of Tonge's comments could only have been to express some kind of identification with Palestinian suicide bombers.
There are good reasons why blandness tends to prevail on such subjects from the mouths and pens of those holding public office. Apart from anything else, the British government might reasonably expect to play some sort of role in a future peace process and it doesn't really help if it (or the parties comprising it) are seen by one side as so partisan that they cannot play the role of honest broker.
So it is right that if Jenny Tonge wishes to continue making the sort of comments on Israel/Palestine that have become her trademark she does so from a position where she is clearly not a representative of the Liberal Democrats.