Britain was struggling before it joined the EEC. In fact, the UK was struggling since the end of WW 2 when it emerged victorious but broke and owing enormous amounts to the US which the US refused to forgive. That was the start of American world domination and the end of British influence. The kind of rah, rah nationalism that drove the Brexit vote is based on the situation more than 70 years ago and ignores how poor the poor were in Britain at that time.