"I don’t approve of what you’ve done,” said my friend, looking up from his Passover preparations, which were characteristically intricate and impressive. As I respected him greatly, I listened with care.

What I had done was put my name to a letter, along with a number of other British Jews, to a public letter expressing “our profound concern and opposition to the judicial reforms in the form tabled by the present government” of Israel.

We had added “our deep concern over the needless and growing division in [Israeli] society that has been created by this process”.

My friend’s concern was twofold. First, that we were giving succour to Israel’s enemies by joining together in such a public expression of disapproval. Second, that the matter was an internal one for Israelis that eluded the full understanding of outsiders, who were best keeping quiet.

I saw the force of both criticisms, but told him that I was unable to accept them. I also mildly pointed out that they were contradictory. One was saying we were too connected to Israel to comment and the other not connected enough.

I then gave him an account of why I had signed the letter, particularly as I usually avoid signing group letters.

Shortly before I was sent the letter and asked for my signature, I had received a copy of Anthony Julius’s new essay, published as a pamphlet by David Hirsh’s London Centre for the Study of Contemporary Antisemitism, that sets out to define and defend liberal Zionism. He had asked me, along with a number of other Jewish writers, to provide a response to be printed with his essay, and I had obliged.

Protest Netanyahu houseF230326YZ02

An anti-Netanyahu protest (Flash 90)

The exercise had made me think about my attitude to Zionism.

I responded to Anthony with two points. The first was to recall the attitude of my grandfather Alfred Wiener to the creation of the state of Israel. In the 1920s, as a German Jew, he had been one of the leading opponents of a state, supporting a home on Palestine but not the creation of a nation.

The Second World War had changed his mind. It made it obvious that a state was necessary. And I had inherited his Zionism. I am a pragmatic supporter of the state of Israel, believing it necessary for the safety of Jews.

But I am also a resolute Briton, not an Israeli, and a strong supporter of liberal democracy everywhere in the world.

Yet, just as Alfred always felt an emotional connection to Jews wherever they live, I care how my fellow Jews behave.

Both of these came into play when I was asked to sign the letter on Israel’s judicial reforms.

I believe strongly in liberal democratic institutions rather than populist democracy. Independent institutions are necessary to act as a brake upon the impulsiveness and arbitrary instincts of politicians and to cool off the hot winds of passing opinions and public mood. They guarantee the rights of the individual against the anger of the crowd.

This is important everywhere. All over the democratic world we see an alarming slide, with the rise of authoritarian leaders and the undermining of legal norms. Jews will ultimately be the victims of this trend and it cannot be in the interest of Jews to remain silent about it.

This is the case even — perhaps especially — when the undermining is taking place in Israel. As Jews who rely upon Israel as the ultimate guarantor of our safety, we are duty-bound to do what we can to protect it.

Part of that duty is to make the case for the country and to explain its need to defend itself when others fail to understand that.

But part of that duty, too, is to make sure that Israel does not destroy itself from the inside and to speak out when we fear that might be happening. Any intervention needs to show restraint and humility.

British Jews may be Jews but we are not, most of us, Israelis. I believe our letter showed that.

Israel will only be a safe home for the world’s Jews for as long as it remains committed to liberal democracy. It’s right to try and protect that.

Daniel Finkelstein is Associate Editor of The Times