At the end of the Second World War, there was a massive displacement of peoples. Millions of Germans were displaced from East to West but so were millions of Poles, hundreds of thousands of Hungarians and, in lesser numbers, minority populations from across the former Russian and Austro-Hungarian Empires. There was then, in the War's aftermath, further displacement of millions as the old overseas empires broke up, most notoriously during Indian Partition. And then, of course there were the Jews.
Each in time settled elsewhere, a good number of the Jews in the USA but the vast majority in Israel.
And, be in no doubt, that displaced other people. Golda Meir's famous slogan "A land without people, for a people without a land" had one significant drawback. It wasn't true.
During the establishment of the State of Israel, some 800,000 Palestinians left the territory Israel initially encompassed, most of them with little choice in the matter.
And, yes, not long after 1948 a similar number of Jews left Arab countries to move to Israel, many of them also far from voluntarily.
The point however is not "whataboutery". It is this. All of this was a very long time ago. And pretty much everywhere else the world has moved on.
Sure, the initial post war platform of Angela Merkel's CDU might have included the "right of return" of Germans to Pomerania and Silesia but it hasn't been their policy for more than fifty years; certainly there might have been a small terrorist war in the Alto Adige/Sud Tirol in the 1970s with reunification with Austria its objective; perhaps the wilder fringes of Hungarian politics might, even now, seek the recovery of Transylvania but essentially it is accepted that people should now have the right to live where they ended up after the tides of war receded. And equally accepted that they don't have the arbitrary right to live elsewhere. Pakistan and India might have continuing border disputes but neither suggests the right of their current citizens to "go back where they came from". That would not be a recipe for peace, it would be a recipe for war.
So, this seems to be accepted in every part of the world. Except one.
Refugees come under the jurisdiction of the United Nations High Commission for Refugees, which defines refugees as those forcibly displaced from their place of birth. Palestinian "refugees" however, uniquely come under the United Nations Relief and Work Agency for Palestine, which defines these refugees, I repeat uniquely, as not only those in the former category (few and far between since they'd need to be at least 70) but also their decedents in perpetuity. The reasons for that have little to do with Israel and everything to do with letting the wider Arab world off the hook.
And this is where support for a fair deal for the Palestinians has to meet the hard reality of what a fair deal would involve.
It certainly involves the right to their own state on (broadly) the pre 1967 borders. And, unless otherwise agreed, the withdrawal of all Israeli West Bank settlements. It also involves some sort of dual jurisdiction in Jerusalem. But it can't possibly involve the "right of return" to a Country in which the vast majority of those asserting this "right to return" have never as much as set foot. For that, in reality, involves the end of Israel as a Jewish state and the consequent displacement of Israelis who have never lived anywhere else.
Now this is where the the Arab/Israeli conflict slips into our own politics. If you are arguing for the Poles to accept the right of the Germans to return to Pomerania: the Romanians to accept the right of the Hungarians to return to Transylvania; the Pakistanis to accept that right for Hindus; or indeed (much more recently) the Croats for Serbs, then your demands would be consistent. But I know of no-one who is making that argument. If however you have chosen to single out one particular small Country for this particular obligation, then you have to ask yourself why.
And here I might surprise you. I don't think it is necessarily as simple as crude and overt anti-Semitism. It is because you are attracted to permanent lost causes. Because causes which are not lost involve inevitable compromise in their solution. And you would then be "tarnished" by accepting that compromise. As, for some on the respective extremes, peace in Northern Ireland "tarnished" those prepared to live with it. As peace with Israel "tarnished" Sadat and possible peace with Palestine "tarnished" Rabin. As, but for the unique figure of the great hearted Mandela, the end of Apartheid always threatened to "tarnish" the ANC.
And also because "success" might show the heroes of your cause to have feet of clay. As, regrettably. has been the case all too often in Latin America.
Take Gaza. Once the Israelis withdrew, it could have modelled itself into what a wider Palestinian state might have become. A democracy (at least of sorts) able to call in economic support by morally blackmailing the rest of the world. Proof that, in one small part at least, a two state solution was a viable end game. But then of course it might instead have collapsed into the sort of corrupt, theocratic or authoritarian regime that exists (sometimes in a combination of more than one feature) in much of the rest of the middle east. So how much more convenient that there was to be no such attempt? That the chief "achievement" of Israeli withdrawal from Gaza was to allow a place where rockets would be launched randomly into Israel and border protests organised for little more purpose than hoping (and regrettably often succeeding) in provoking Israeli over reaction. No compromise but no sell out either. No tarnish. Just the excuse for continued grievance. Applauded from afar by those with little politics than continual grievance themselves. No matter what needless misery that might entail for those more directly involved.
So, is Corbyn an anti-Semite or just someone perpetually attached to hopeless causes? Probably a bit of both. In support of the former conclusion, he could for example have promoted the equally hopeless cause of the Kurds. Or the Burmese Muslims. But he has notably not done so. My principal problem however is that, under Corbyn, Labour itself has become a hopeless cause and I increasingly wonder if that is not his hope but his objective.
He's not so stupid as not to appreciate that failure to enjoy any meaningful poll lead in current circumstance bodes disaster when the Tories get their act together, as, inevitably, they will. And he must realise that the determination of some of his allies, at least, to provoke a formal split would be a lunacy that might finish off the Labour Party itself. He surely realises that the current anti-Semitism problem is not one of his opponents' making but rather one of his own. And that, whatever its rights and wrongs, it is electorally toxic and can only be resolved by his compromise.
But perhaps he genuinely doesn't care? Had we won on the 2017 Manifesto, we couldn't possibly have delivered on the public spending and public sector wish list that underpinned it. Compromise (and disappointed outrage) in government would have been inevitable. Never mind that, we'd have needed to sort out Brexit. Tarnish would have been inevitable. So perhaps he actually wanted to lose? Perhaps he actually wants to lose again.
For, of course, there is no need to compromise from the position of permanent opposition. You will never be tarnished.