"In reality, the long history of unionisation ... is replete with homegrown racism..." [updated]

"In reality, the long history of unionisation in the United States is replete with homegrown racism, as organised labor has sought to increase white workers’ wages by driving African Americans out of the competitive workforce. Many early-20th-century union initiatives, including working-hour restrictions, minimum wages, and collectively codified seniority privileges for existing workers allowed organisers to cartelise white labor against wage competition from African Americans and immigrants. The mostly white union sector benefited from artificially higher pay under these measures, whereas blacks found themselves excluded from employment entirely."

~ Phil Magness, from his article 'The 1619 Project's Confusion on Capitalism'

“It’s impossible to understand early twentieth-century progressives without eugenics. Even worker-friendly reforms like the minimum wage were part of a racial hygiene agenda… The minimum wage, in addition to providing some workers with a better standard of living, would guard white men from competition.”

~ Malcolm Harris from his article 'The Dark History of Liberal Reform', reviewing the book Illiberal Reformers: Race, Eugenics & American Economics in the Progressive Era  

"Racist views were widespread in New Zealand [too] during the nineteenth century but it was in the Labour movement that these views received their fullest expression. The emotive appeal of nationalism, the social Darwinist vision of the battle of the races and feared economic competition fused in the Labour movement to produce a series of anti- Chinese campaigns. Racism in the Labour movement peaked in the early twentieth century when the White New Zealand policy was established. Regulations which discriminated against groups on a racial basis were a feature of trade unionism in New Zealand from its early beginnings and these policies were defended in this period with great vigour by Labour racists."

~ G.R. Warburton, from his 1982 Masters thesis 'The Attitudes and Policies of the New Zealand Labour Movement toward Non-Union Immigration to New Zealand, 1878 - 1928' (p. 179)

"The Auckland Labour MPs were spurred by the Grocers' Assistants and the Furniture Trade Union into sending a telegram to [then] Prime Minister [Massey] protesting that all this cheap [foreign] labour would lower living standards and probably lead to deterioration of the physical vigour of the race. M. J. Savage was particularly alarmist. The teeming millions of the East were less than a stone's throw away and New Zealand was faced by a rushing horde of Asiatics which it must try to stem both by laws of its own and by negotia- tions with Asian governments themselves. The Auckland Water-siders also recorded their fears for the living standards of the workers and their abhorrence of the 'piebald New Zealand' which now threatened..."

~. P.S. O'Connor, citing Auckland Star reports from 1920, from his 1968 article 'Keeping New Zealand White, 1908-1920'

 UPDATE:

The airbrush has been applied to some of this history. As Duncan B. points out, this verse from long-lived Australian folk song 'Travelling Down the Castlereagh'* has been bowdlerised in recent years:

I asked a cove for shearin' once along the Marthaguy

"We shear non-union here," says he. "I call it scab," says I
I looked along the shearin' floor before I turned to go
There were eight or ten non-union men a-shearin' in a row

The original verse ended:

There were eight or ten dashed Chinamen a-shearin' in a row

"Pretty clear from the original, says Duncan, "what the union was about, at least in part."

* First published under the title 'The Bushman's Song in the Bulletin in 1892. This poem of Banjo Paterson's has grown a number of tunes in its time in the bush. Meredith collected three tunes in NSW, and two tunes are given in the Queensland Centenary Pocket Songbook while in his Big Book of Australian Folk Song Ron Edwards gives another two. This tune is the one most commonly sung today, and was collected separately by Geoff Wills and John Manifold. Manifold got it from Mr Hines of Donald, Victoria, it is in his Penguin Australian Song Book.
See also 'The Bushman's Song' in the Evening News 1870.