A clear shift in public discourse around Israel is unfolding in the United States. Americans are increasingly disapproving of blank checks and uncritical support for Israel. Growing numbers of people embrace the Palestine movement as an organic part of any left or progressive movement. Yet there remains one area of Palestine advocacy that is still considered taboo, one even progressives often are scared to touch: support for the Boycott, Divestment, and Sanctions movement (BDS) and its call to defund apartheid and military occupation.

Over a hundred seventy Palestinian civil society organizations, representing Palestinians across the diaspora, in the West Bank and Gaza, and Palestinian citizens of Israel, have called for a boycott of, divestment from, and sanctions on Israel until it complies with international law. The call was formally launched in 2005. The BDS movement’s demands are concrete: Dismantle the apartheid wall and end the occupation of the West Bank and Golan Heights, recognize the full rights of Palestinian citizens of Israel, and uphold UN resolution 194 which stipulates,

…refugees wishing to return to their homes and live at peace with their neighbours should be permitted to do so at the earliest practicable date, and that compensation should be paid for the property of those choosing not to return and for loss of or damage to property which, under principles of international law or equity, should be made good by the Governments or authorities responsible.

The Boycott Apartheid South Africa movement, a main source of inspiration for BDS advocates, took over thirty years to gain traction and spread from small grassroots campaigns to eventually shifting state policies toward and major corporate investments in South Africa. BDS also builds on the rich tradition of boycotts and strikes within Arab liberation struggles across the region spanning decades. It is estimated that Arab boycotts between 1948 and 1994 cost Israel $40 billion.

Operating principally in the academic, cultural, and economic realms, BDS has been adopted by a wide range of institutions — unions, academic associations and institutions, churches, and even several city councils. In the United States, it’s been adopted primarily on college campuses and church organizations. In 2015, the eight-hundred-thousand-member United Church of Christ passed a resolution calling for divestment from companies profiting off of Israel’s atrocities against Palestinians.

Targets of BDS campaigns include corporate giants like G4S and Elbit Systems. These are good examples of the ways in which BDS could have international impact. A boycott of Elbit Systems would affect construction of surveillance technology on the US-Mexico border and Israeli military checkpoints. These campaigns can help expose the role of private corporations in supplying states like Mexico, the United Arab Emirates, Bahrain, Honduras, and India with technology used to repress, surveil, and imprison their populations.

Israel leads in security technology development globally and is the world’s largest arms supplier per-capita, testing them on Palestinians before exporting to other countries. Adam Hanieh argues, “It is not merely the depth of suffering or length of exile that makes the Palestinian struggle an imperative of international solidarity in the current period.  It is also the central location of the struggle within the broader context of global resistance to imperialism and neoliberalism.”

US financial and political support for occupation is based on joint economic interests and shared investments in military and arms. The annual $3.8 billion in US military funding to Israel comes with a stipulation requiring a percentage of the funding be used to purchase US-made weapons. In fact, the United States is the single largest arms supplier to Israel and paid almost single-handedly for Israel’s Iron Dome System. The US government diverts any attempt to hold Israel accountable for its atrocities and war crimes against Palestinians, and supplies it with unprecedented military funding packages, more than the next ten countries combined.

There’s a reason Israel is so fixated on the particulars of US politics: With financial and political backing of the world’s largest military power, Israel is able to whitewash occupation, settler brutality, home demolitions, and a thirteen-year-long blockade on Gaza with US tax dollars.

Critics on the Left have raised questions about what Palestinian workers think about BDS campaigns and whether they can inadvertently alienate some of the hundred thirty thousand Palestinians who work in Israel or its illegal settlements. Manal Shqair, an organizer with the Palestinian New Federation of Trade Unions explains why even workers whose employers are subject to boycotts support BDS:

Palestinian workers oppose the assumption that international support for the BDS movement might harm Palestinian workers who work for companies targeted by BDS. On the contrary: the dismantling of the Israeli settlement enterprise means that we Palestinians will be able to reclaim our land and natural resources. This, of course, will put an end to the exploitation of Palestinian workers by their Israeli employers. Any argument against this is an anti-worker argument.

Another question often posed is whether the movement is effective. Although still small-scale, there are many examples of the impact BDS has already had in shifting public opinion on Israel and disrupting corporate investments in apartheid.

Its effectiveness and potential can also be gauged by the ruthless response it has triggered in Israel and its partners, who make BDS out as a powerful sweeping force, though the movement is not yet as robust and widespread as it has the potential to become. Supporters of Israel have spent a great deal of money and influence to marginalize, persecute, and threaten all those who engage in BDS campaigns.

Most famously, the late right-wing billionaire Sheldon Adelson’s Maccabee Task Force raised tens of millions of dollars to combat BDS on college campuses. It is also no coincidence that the online blacklist Canary Mission launched in 2015, around the same time BDS campaigns were introduced in several major colleges.

Anti-boycott laws targeting Palestine advocacy have been enacted in thirty states. In 2016, New York governor Andrew Cuomo took a page from the McCarthy-era playbook of blacklisting communists by signing an executive order directing NY state to keep a public register of organizations involved in boycotts of Israel — and mandated that all state agencies under his authority dissolve financial ties to those organizations.

This response to BDS suggests the massive impact the movement could have on capital flow to Israel. BDS is not merely about propagandizing or taking a moral stand. It’s about having an impact on material support for ongoing apartheid by pressuring governments and corporations to withdraw political and financial backing or else risk economic loss. For the United States in particular, BDS comes in the way of its vision for a united economic zone that integrates Israel into the Middle East economy.

Boycotts can work. The power of boycotts past and present is that they refuse to confine the movements they represent to the realm of humanitarian relief — they also demand accountability. Last week, Human Rights Watch released a 213-page report charging Israel with apartheid and crimes against humanity. It’s long past time to hold Israel accountable. BDS is a movement to disempower and defund such crimes — and that is a movement worth supporting.