“Injustice anywhere is a threat to justice everywhere.” Martin Luther King’s observation, written half a century ago from a jail cell in Birmingham, Alabama, is as true today as ever. And it goes to the heart of why Palestine is an issue for workers in Australia.

History confirms that revolts against imperialism help workers in imperialist countries. For example, the colossal defeat suffered by the United States in Vietnam was a major factor in the radicalisation that swept the world in the late 1960s and early 1970s, contributing to workers’ strength in many countries, including Australia.

Sometimes the connection between different battle fronts is very clear. Cops who have turned Ferguson, Missouri, into a war zone over the past fortnight were trained by Israeli security forces.

Last year the Australian Federal Police signed a $35 million contract with Israel’s largest private arms company, Elbit Systems, for the supply of “an Investigation, Intelligence, and Incident Management Solution”. Tactics and technologies perfected in Israel’s surveillance, repression and outright slaughter of the Palestinians are then used to repress ordinary people around the world – from Ferguson to Australia.

The rich and powerful around the globe constantly support each other in their efforts to keep the rest of us in our place. So it stands to reason that the rest of us have an interest in solidarity with each other.

There was a time when this view was widely shared in the trade union movement, and found expression in widespread support for the struggle against South Africa’s apartheid regime. When the all-white South African rugby team toured Australia in the early 1970s, union after union banned their members from giving them any assistance. The maritime unions in Australia were famous around the world for their sanctions on South African cargo.

In the 1980s the militant Builders Labourers’ Federation toured anti-racist South African speakers around work sites, raising money and support. The BLF was instrumental in a years-long trade union picket of the racist South African embassy in Canberra. Other unions played a less active role, but would turn out for protests and carry articles in their publications supporting the freedom struggle in South Africa.

As Israel’s gigantic, bloody, crimes unfolded in Gaza over the past month, however, it became clear that Australian unions’ attitudes to apartheid Israel fall well short of matching this proud history.

At one level, the reluctance of many in Australia’s union movement to condemn Israel’s bloody slaughter seems strange. After all, many unions have a substantial membership among workers who feel ties of faith, family or history to the Palestinian cause. In contrast, no Australian union has a significant Zionist current among its membership.

However, there are a number of factors that get in the way of Palestine solidarity in our unions. The political left centred on the various Communist parties played a major role in Australia’s unions for decades and provided a mainstay of support for international solidarity. The disorientation and collapse of this left, accelerated by the implosion of Stalinism worldwide at the end of the 1980s, created a political void in the workers’ movement. And years of defeat and retreat in the unions have helped a more conservative “common sense” to take hold.

Added to these factors is the strength of pro-Israel sentiment among Australia’s elite. Support for Zionism, along with the US alliance, is among the most sacred foreign policy positions of the Australian ruling class. Any party that aspires to government – including the Australian Labor Party – understands that criticism of Israel is not to go beyond a few token statements. This has an impact on the vast majority of union officials who want to manoeuvre within the ALP.

All of this helps to explain why, while a small number of unions took a forthright stand against Israel’s slaughter in Gaza, many more ducked for cover.

Even the shelling and then total destruction of the al-Wafa hospital, which had been assisted over many years by the ACTU’s aid organisation, was not enough to prompt the ACTU to issue the mildest “tut-tut”.

Most unions took this as their cue to do nothing. Those unions that took a more forthright stance were either on the political left or had a history of solidarity with the people of Palestine, or both. Shaun Reardon, Victorian assistant secretary of the CFMEU, on 17 July posted the following on the union’s Facebook page:

“When I was last in Gaza, I enjoyed the warmth and hospitality of the Gazans on the one hand, and I witnessed the effects of ongoing physical and emotional trauma inflicted on them by the Israel Defence Force on the other. When I see the current footage of Israel’s assault on the people of Gaza, I immediately think of the impact that this violence will have on their children and I’m thankful that my children have grown up free from these dangers.

“The military imbalance between the people of Gaza and the Israeli Defence Force is shocking and the number of Palestinian deaths is criminal … On behalf of the CFMEU I extend a message of solidarity to our comrades in Palestine and Israel who share our desire for peace and justice.”

The Victorian branch of the Health and Community Services Union put out a statement that called for the lifting of the siege and condemned Israel’s deliberate targeting of health workers and institutions.

Easily the most visible union supporter of Palestine has been the Maritime Union of Australia, reflecting the long history of militancy and international solidarity in the maritime industries. MUA representatives addressed Palestine solidarity rallies in Sydney, Melbourne and Perth, while MUA Victorian secretary Kevin Bracken proposed a motion, unanimously endorsed by Victoria’s Trades Hall Council Executive, which condemned Israel’s attacks, restated VTHC’s support for boycott, divestment and sanctions against Israel, and endorsed community protests.

Other unions to issue statements critical of Israel include the Australian Education Union, the NSW branch of the Fire Brigade Employees Union, the Victorian branch of the Rail, Tram and Bus Union, the Sydney Uni branch of the National Tertiary Education Union, the Melbourne delegates’ committee of the Australian Services Union Social and Community Services division and the Electrical Trades Union.

Socialists are proud of our role in all of this: of the recent motions and statements listed on the Australian Unionists Supporting Palestine website, Socialist Alternative members have had some part in more than half. But of course, the greatest motion on Earth is only words on a piece of paper.

The point of this activity is to get political discussion in our workplaces – because this is where political sentiment, combined with union organisation, can ultimately lead to effective action. So as well as pushing our unions to take a public stand on Palestine, we talked with our workmates about the issue, countered the propaganda offensive in the Murdoch press with Red Flag, did several workplace collections and agitated to get workmates and fellow unionists to the demonstrations.

The ongoing project of building Palestine solidarity is tied to the overall state of our unions, the class struggle and the left. The more confident and better organised we are in our workplaces, the more we are able to support our brothers and sisters elsewhere – on the other side of town, interstate or internationally.

Organising meaningful solidarity has always depended, in large part, on the strength of militant, socialist political forces. So the painstaking work of building a socialist organisation, and rebuilding a socialist current in the workers’ movement, is essential work in strengthening our global front line – from Australia to Palestine.