If socialism has failed, it is failed to achieved 'equal' opportunity. But so-called 'capitalist' countries have also failed in this regard.
Socialism has failed because it is unrealistic to rely on people taking care of other people's interest as well as their own.
In france, it has not failed, it adopted a strategy of immigration to increase its electoral base and that was a good strategy for him.
It allowed
.to divide the right between the extrem right and the right
.it provided with long terms electors with the higher birth rate of the immigrant population, who are massively left
.and it helped to maintain poverty which is the necessary ground to explain its thesis
The official thesis for immigration evolved among the socialists from :
.Immigrants will have no difference with the french with time (the "integration" phase)
Even after fighting hard people who did not think that, by numerous association (MRAP, 'Touche pas à mon pote', LDH, etc,..) it was clear that this would not happen, so they change to phase 2
.Immigrants are different but it is good (the "diversity" phase)
Here again, they fought a lot people who dared thinking otherwise, and in the meantime the tap was on, with massive immigration going on.
For instance when the jews were being beaten, socialist had a very hard time admitting it was immigrants doing this, because it was contradicting the line of the party presented above. In the sametime, a few sordid stories of french being beaten to death for nothing came out.
This old guy Paul, retired and poor, got beaten and his house burned down days before the presidential campaign.
A woman called "supermamy" in her neighborhod had her throat slitted.
(that is just 2 I remember right now form that period)
Of course the politbureau attacked Paul for being an extreme right etc...
But the official line was undefendable when the word "insecurité" became the periphrase for the threat coming from the banlieue. Which lead to the 3rd phase.
.There are some problems in the banlieues and it was forecastable
This thema was brilliant as it enables to collect the support from the ex communists movements who were orphaned since the disclosure of the immensity of the disaster they supported. The new exploited was the immigrant, which enabled to federate the left, and strategically profit of the demography dynamic.
It fully adheres to the third world rethoric to say that french spoiled those people, parked them in towers, while they used them during the properous years, and they let them do the "dirty works".
Of course it disregards that those towers are being payed and given by the french, that there is no obligation of residency there, that mass immigration started well after the prosperous period, that other country with no immigration also had those years, and that they too have roads, that many french workers would be happy to build roads if that was not for african salaries and thousands of people lining up at 5am to find a job for the day, that no one invited the immigrants to come, that if they travel one way, they are also free to travel another way, etc...
So the good news is that everyone agrees on the conclusion :
.There are some problems and it was forecastable
Now of course the left attributes this fault to french, while the right, well, it was always their forecast.
Now the open questions are :
.What will be the next theory?
.Will it come with troubles?