In 1919, dockers in the city of Seattle refused to load arms for use against the recent Russian Revolution. They were followed by dockers in San Francisco, London, Hull and elsewhere.
In that same spirit of global solidarity, Lancashire cotton workers supported Abraham Lincoln in the American Civil War, understanding that the war was against slavery. In 1889, Australian and other workers sent financial support to the great London dock strike. The recent refusal of Scottish train-drivers to move war materials was another example of a vital tradition.
International solidarity has a long and honourable tradition in the labour movement. It is central to the idea of socialism. Workers can and do recognise, against the barrages of nationalist propaganda, that they truly 'have no country', as Marx wrote in 1848. Their real kinship is with other members of their class across the world.
Now, more than ever in history, capitalism is a global system. It can only be transformed into a different world through international solidarity among workers. There can be no 'socialism in one country'. Of course, internationalism is not the only current within the popular mind. We're bombarded daily with what seem 'common sense' images. They support the idea that we belong to a nation and that this nation must compete with other nations.
In sport we're supposed to identify with 'our' team. In culture, we must cheer when a 'British' film does well in the Oscars. We're even supposed to value education because it will 'make us competitive'-so SATs must be imposed on our kids in school, and top-up fees on our students. We must back imperialist war because 'our boys' are over there blowing Johnny Foreigner to bits.
What does nationalism assert? That we, as 'the British' or 'the French' or 'the Ruritanian' people have more in common with each other than we have with people from 'outside'. So the exploited worker has something in common with the rich company director or the landowning Duke? Nationalism ties us all together under a particular nation-state, and divides us as a class.
That nationalist strand in 'common sense' is not the only one. The opposing strand arises from our common experience of exploitation and domination. Ordinary people's capacity to empathise with others, regardless of nation, colour, religion and the rest, appears in all manner of forms.
Older readers will remember how images of famine in 1980s Ethiopia were captured and crystallised in mass sympathy by Live Aid. Black people's struggle against apartheid in South Africa attracted immense worldwide solidarity. Today, hundreds of millions identify with the Palestinians as symbols of resistance to injustice.
As in economic life, so in politics and ideas. There are two impulses in every worker's experience. One responds to the competitive character of capitalism, to worries about getting or keeping a job, to fear and isolation. That impulse produces division and weakness in our movements.
The other impulse involves recognising a brother or sister in the suffering and struggles of the exploited and oppressed across the world. It is the impulse to solidarity, reaching across borders.
That inner war between rival tendencies is expressed in labour movements. On one side, 'moderates' want unions to bow to employers' need for profits, to back 'our country' at war, to 'defend British jobs' when companies threaten to move production abroad to cut wages.
On the other side stands the socialist left, arguing against sweetheart deals with bosses, opposing imperialism, seeking to both defend jobs and develop solidarity with workers in other countries. For socialists, the struggles against the war on Iraq and against the war on asylum seekers are the same struggle.
Not simply-true though it is-because we are the 'nice people' who are against imperialist slaughter and robbery and against every manifestation of racism, but because we know that the interests of our class are always internationalist.
I began with Seattle back in 1919. Let's swing back there 80 years later. In the last major act of the 20th century, a brilliant new spirit of internationalism was reborn in the demonstrations against the World Trade Organisation. Seattle in 1999 brought together a host of quite disparate campaigns and issues.
Its significance lay, not least, in the links that previously distinct groups of activists found between their struggles. Their very coming together posed new questions about how mass campaigns could identify and confront common enemies. The early years of our new century have witnessed immense anti-war movements on a scale not seen since the revolutions that ended the First World War.
At huge international forums, a brilliant new generation of activists have joined to debate the way forward for movements of emancipation. They take international solidarity for granted. They identify global capitalism as the key enemy.
Who would have predicted, only five years ago, that we would see trade union delegations going to Paris or Mumbai to forge links across continents and across the globe? A new era has opened, with immense revolutionary potential.
The anti-capitalist and anti-war demonstrations, and the international forums, prefigure a new internationalism from below that will grow in ways we can, as yet, barely imagine.