“Welcome to Ecuador. We do not want any anti-Semitic incidents, so please would all the men remove their kippot and wear caps instead.” It was a strange and sad opening to my kosher trip to South America.

When asked about it, our tour leader explained, “There is so much anti-Semitism all over the world now, I cannot take risks with any of my groups, anywhere. Wherever I lead a Jewish group, I have to ask them to remove prominent Jewish symbols.”

Her policy reflects the ever-increasing reports of anti-Semitism in Europe and around the world. Fuelled by the Gaza war, anti-Semitism seems back in vogue.

It is against this background, that we must measure Ha’aretz journalist Gidon Levy’s comments, which were repeatedly screened on Sky News last week.

Mr. Levy condemned Israel’s bombing of Gaza which he suggested inevitably led to an unacceptable number of civilian casualties. He then went on to claim that whereas previous wars had been accompanied by an intense moral debate in Israel, in this war, Israelis did not even bother to question what our army was doing.

He was wrong in his reading of Israelis, unreal in his expectations and dangerous in his accusations about our people.

Whether or not we agree with him, Mr. Levy is an important voice in Israel. We should admire his willingness to court unpopularity and to defend some of our most important values. True biblical prophets acted as moral watchdogs in contrast to the false prophets who merely parroted the government’s line, repeatedly reassuring the Jewish people how wonderful they were.

The Israeli peace movement continues to play an important role in advancing the push for peace wherever we can find a reliable partner. We should respect and even treasure its activities in ensuring that Israel remains faithful in its commitment to seeking peace, just as we should respect the valuable contributions made by right wing commentators and politicians in a Left leaning government.

But, while Mr. Levy raises valuable questions, there is surely a difference between challenging us to ensure the ethical character of our military and turning one’s back on one’s own people. There is a line between constructive criticism which might lead to positive change and scathing public attacks on our nation which will only empower our enemies.

Reasoned rebuke in peaceful times is completely different to verbal assaults on our people when they are under attack and soldiers are fighting at the front to defend us. It is hard to see any positive outcome from slandering our people on a news network which poison the minds of millions of people and embolden our enemies, but has no impact on our own decision makers. In the light of these differences, we have to ask at what point the fair rebuke of an insider turns into the destruction wreaked by a turncoat?

In our tradition, the moser or Jewish traitor was the most detested figure of all. We should never use that charge lightly. To do so is to censor all criticism and to invite witch-hunts. We cannot preserve democracy unless we are willing to tolerate critical voices. We cannot maintain our morality unless we are willing to hear alternative opinions and pay attention to their complaints.

Mr. Levy’s war commentary contained nothing new. Even amongst the hawks, there is universal agreement and determination that civilian casualties must be limited as much as possible. It is true that there has been awful destruction in Gaza and much suffering, but it is also undeniable that Israel has gone to enormous lengths to prevent unnecessary suffering. But when rockets are stored in schools and hospitals, then fired indiscriminately into our country and when tunnels are dug under our borders for the purposes of carrying out kidnappings and terror attacks, the aggressors must be neutralized, there is no alternative. As our rabbis taught, before going to war, Jewish leaders must first sue for peace, but once a defensive war has started, a Jewish army must fight with determination.

Israel may be a nuclear power with a strong army, but so long as we refuse to use this firepower or even to threaten its use, we remain vulnerable. The accusation of disproportionate use of force by Israel rings hollow in the light of Hamas’ sustained desire to continue fighting for weeks and its unquenchable thirst for sending rockets to kill Israeli civilians.

It may be that Mr. Levy’s comments were taken out of context. But in a hostile environment where desperate enemies plot our destruction, when sanctions are threatened against Israel and when Jewish communities are being attacked across the world, all of us must have a sense of responsibility. Indiscriminate criticism of our country in a hostile media is a luxury we cannot afford, at least until our people in the South of Israel, South America and everywhere else can live their Jewish lives openly and without fear.