With all the lamenting of Britain leaving the European Union, the EU is portrayed as a sanctuary of sanity and decency in a mad and bigoted world. There were some elements of truth in this, but increasingly the EU was a powerful force for neo-liberalism.
Given the EU's comprehensive regulations embedding capitalism into its structure and forbidding State intervention, it is quite likely that the introduction of Socialism into Britain would have required leaving the EU.
Yet imagine a newly formed Socialist government trying to leave the EU. There would have been uproar and opposition from all sides (including the liberal left and many left-leaning social democrats) and vested interests that could easily destroy the government.
This critical step of leaving the EU has now been taken, for the wrong reasons certainly, but it does make the introduction of Socialism that little bit easier.