Is Naz Shah an antisemite? Her political career hangs on the answer to that question. But there's something larger behind it too. Her attitudes are far too common among British Muslims. If she's an antisemite, there are many others like her.
Then there's the question of whether she can change. She has apologised but does that mean she won't show her attitudes again or that she will try to change them? I hope it's the latter; though, if antisemitism is a question of one strike and you're out, then that's the final word on her, and might be the final word on me too.
I grew up with antisemitic attitudes being commonplace around me. I remember long, rambling conversations with other teenagers, and adults who should have known better than us, that started with Palestine and criticism of the Israeli state, then ranged through conspiracy theories and jokes that make me shudder now.
Theoretically, if I go back to those conversations, then I can draw a line between the parts that were anti-Zionist and those that were antisemitic. But we never did in practice. There were two reasons for that. The first is that, as too often in political discussion, the point was to egg each other on. No one wanted to be the spoilsport that sounded the alarm. The second reason was that none of us knew any Jews. Suggesting, for example, that Jews living in Israel could all be moved from there to the US was weightless, as well as witless, because we didn't know anyone who might be affected by it.
Though, even as I write that, I can judge that it's a poor excuse. I knew perfectly well that our conversations were morally corrupt. But there is still a difference between knowing what views are beyond the pale and having a stake in challenging them.
What gave me that stake was starting to encounter Jews. First it happened through the pages of books: fiction writers like Saul Bellow and Philip Roth. I went to university and made friends who were Jews. Then I made a mistake. I published in our student magazine a supposedly satirical article suggesting that one of our lecturers secretly owned one of the university buildings. You've guessed it. He was Jewish. He explained to me what I'd done. I was mortified. I hadn't noticed he was Jewish. I didn't know the history of these slurs. I admired him and yet, as he spoke to me gently but with anger too, I watched myself drop 50 floors in his estimation.
After all that, am I an antisemite now? I hope not. My best guide is that I was living in Lebanon before the Israel-Lebanon war in 2006 and, even as the air strikes came in, I could make the difference between criticising Israel and maligning Jews.
What I've learned is that antisemitism disappears gradually; and only upon close contact. But then there are many more Muslims in the UK than Jews. Do you have to do the work of getting to know them, changing their views one by one through prolonged effort? It's hardly practical, especially not when many British Muslims have everyday lives in which they don't make much contact with Jews.
This is why it's important that I contest antisemitic views when I hear them too. And why Naz Shah should get her second chance: if her apology is sincere, then she should get stuck into the task of changing the views of those around her.
It is this everyday liberalism that provides the best hope for changing attitudes: calling out the views of those who close to us as unacceptable when they are so; finding ways to know people from communities you might otherwise find it easy to distrust; and letting your jaw drop when you make a mistake rather than hoping that no one notices.
Corbyn's Labour - what you need to know. Don't miss the special issue of the JC, out this week, including comment from Howard Jacobson