It is no overestimation to say that the intermodal container is enormously significant to the modern shipping industry. Before its widespread introduction, transporting break bulk cargo involved a lot of hard, time-consuming and expensive manual labor. What happened to the people employed to perform that labor? Did unions attempt to shut down or otherwise fight against the use of standardized containers for fear of these workers being out of a job?
I can't really give a worldwide or even national view of this, but I can give you a very local one as the city I grew up in (Hull, UK) was massively affected by the change.
First a little bit of background, Hull is in the North of England on the River Humber which is the largest estuary in the UK. Through the Second World War it was an extremely important port both for fishing and cargo and ship building location, and was exensively bombed by the Germans because of this.
When the shipping container was being introduced this caused a great deal of strife with the Labour unions representing dock workers who objected to the potential job losses. There were numerous strikes and labour disputes which got pretty ugly.
In the end almost all of the shipping jobs in Hull went, because instead of modernising the existing port they built a new purpose built container port on the other side of the river at a place called Immingham. That is now the main port for the whole estuary.
The fishing industry survived for a couple more decades before being destroyed by the Cod Wars, and Hull ended up like many post industrial cities, with a lot of poverty unemployment and the associated problems.