As with everything else, Jeremy Corbyn believes that literally everything bad is the fault of “capitalist democracy”. Or, in this case, with “unscrupulous employers”. Mass immigration and even open borders don't create any problems whatsoever – only “capitalism's failures” do.
Thus when Corbyn (in June 2016) was asked about the problems of immigration, he had this to say on the virtues of staying in the European Union:
“Let's not turn this into blaming people who travel, work and migrate around Europe, let's instead ensure governments respond to the needs of all communities and that unscrupulous employers that are grossly exploiting migrant workers and trying to limit their rights need to be dealt with.”
In other words, with some very neat steps, he completely changed the subject. The subject for Corbyn and other socialists (as ever) isn't mass immigration, dozens of Muslim ghettos, frequent terrorism in Europe, indigenous unemployment, Muslim rape-gangs, possible civil war in the future and falling wages because of immigrants. The problems are “unscrupulous employers” and the lack of “rights” for immigrants. Indeed, as an International Socialist and therefore a person who believes in open borders, how can there ever be a problem with immigrants? There can only be a problem with our political system, closed borders and employers.
Like the anti-white racist Diane Abbott, Corbyn believes that to simply open one's mouth about immigration is to be a racist. Or, in Corbyn's own words, “the usual racist pap about immigration causing problems and pretending that the unemployment figures... were caused by immigration”.
If racists are dumb because they argue that all things bad are created by immigration. Then are socialists also dumb when they say that nothing bad can come from (mass) immigration? Take your pick and make sure you base it on your political biases.
Corbyn also becomes more extreme and generalised. He said that there are no “cultural changes that have taken place because of immigration [which are] are unacceptable”. Really? Where does Corbyn live? Where did he live as a kid?
And then - when responding to someone who dared to bring up immigration - Corbyn swoons in his own piety and grandstanding anti-racism when he tells us:
“I find his remarks offensive and unacceptable, as do people... who are not prepared to put up with that kind of bigotry.”