Amid the ongoing uproar over Israel’s actions in East Jerusalem, another Israeli injustice was overlooked on Monday, one that took place halfway round the world but has important and wide-ranging implications on the ground. Five Americans were prohibited from boarding a flight from the US as part of an interfaith delegation that was to meet with religious leaders and human rights activists in Israel and Palestine.

This might not seem like a particularly noteworthy incident in the grand scheme of the Israeli-Palestinian conflict, particularly amid current tensions and violence. But its significance is derived from it not being an isolated incident.

It is the manifestation of a law that Israel’s Parliament recently passed, which prohibits entry to supporters of the Boycott, Divestment and Sanctions (BDS) movement (the law leaves the definition of support deliberately vague and open to interpretation). These Americans are just the latest in a series of people worldwide denied entry under this law.

The claim by Israel and its allies that BDS is anti-Semitic — that tired old accusation to silence valid criticism of Israel — was always ridiculous (that, however, did not stop German Chancellor Angela Merkel’s party labelling BDS as such in December 2016).

But this week’s incident is a stark example of just how absurd this claim is. Three of the five Americans who were prohibited from flying to Israel are Jewish (members of Jewish Voice for Peace). One of them — Alissa Wise — is a rabbi. “Israel denied me the ability to travel there because of my work for justice for Palestinians, even though I’m Jewish and a rabbi,” she said.

The law is part of a domestic and global effort to crush a non-violent, grassroots movement that has grown in leaps and bounds since its establishment in 2005. Initial dismissal of BDS as a fringe movement has turned into acknowledgement by senior officials from Israel and its allies that it poses the biggest strategic threat to the country.

But the law has wider implications for Palestinians. In addition to the myriad physical barriers — checkpoints, walls, settlements, blockades and Jewish-only roads — that keep Palestinians penned in like caged animals, this is yet another method of cutting them off from the outside world. It is not as visible but just as invasive.

Israel has long restricted Palestinians from traveling outside the open-air prison that is their homeland, unless of course it is to leave permanently. But with this law, now more than ever they are denied visitation rights. As Israel separates Palestinian communities under its control from each other, this law also further separates them from the global diaspora.

One of the most mutually enriching aspects of my visits to Palestine was swapping experiences and perspectives with those under occupation. We learned from each other and cemented national bonds with personal ones.

Those who back the Boycott, Divestment and Sanctions movement will not renounce it or hide their support for it, even at the expense of being cut off permanently from Palestine. This is a small price to pay compared to what Palestinians are enduring and sacrificing.

Sharif Nashashibi

For outsiders such as myself, it was invaluable to see and experience first-hand the daily indignities and heartbreak of life without basic freedoms, but also to see the humanity of a people dehumanized by its oppressors, the generosity of those who have lost so much, and their spirit and resilience in the face of relentless subjugation. These people are at the same time extraordinary yet also, in many ways, just like you and I. One must experience this dichotomy in person to fully appreciate it.

For Palestinians under the longest military occupation in modern history — half a century and counting — such visits provide reassurance that they are not alone, forgotten or abandoned, and that their cause resonates worldwide. In the case of the Americans barred this week, imagine the bridge-building value of occupied Palestinians meeting Jews — including a rabbi — who oppose their plight, rather than just those who enforce it.

One should never underestimate the sustenance that hope can provide. Israel is well aware of the value of such contact, interaction and exchange. It thus realizes the importance of denying them in pursuit of its propaganda efforts and divide-and-rule strategy. That is where this law comes in.

The effect on me, for example, as a BDS supporter, is that as long as the law is in place — and I see no circumstance on the horizon in which Israel would repeal it — I will never again be able to visit my homeland, from which my father and his family were expelled in 1948, and in which I still have dear friends and relatives. Indeed, since the law was passed, I was unable to attend the wedding of one of my closest cousins.

There are countless others in the same situation. It is difficult for us to adequately describe the feelings of resentment and loss over the forced separation from one’s own people and homeland because we have the audacity to seek their freedom. But this resentment will never breed resignation; just as almost 70 years of exile have not diminished the diaspora’s identity, neither will physical separation impact our deep connection to Palestine.

Nor will this law thwart BDS. On the contrary, it will galvanize the movement to face its increasingly desperate opponents. Those who back BDS will not renounce it or hide their support for it, even at the expense of being cut off permanently from Palestine. This is a small price to pay compared to what Palestinians are enduring and sacrificing.

For foreigners and the diaspora, this is our form of resistance, a legitimate and increasingly effective one over which Israel has relatively little control, and one that we will never abandon as long as justice is denied.

• Sharif Nashashibi is an award-winning journalist and commentator on Arab affairs.