A united (ha ha) liberal (double ha ha) Europe doesn't work for all though does it, that's why Leave won. If you cannot see that is why Trump got in (and will again if he runs in 2020), and why there is disaffection with the EU, then you need to clean your glasses/give your head a wobble etc.
There is a massive disconnect between the governed and the governing. Many of those who espouse the liberal consensus are sitting in their Brussels bubble/M25/Westminster bubble and haven't got a fecking clue. On paper, I should have voted Remain, but I didn't, because if you look very closely, the fault lines are there for all to see. The EU (and it is different to Europe) is trying to shoehorn nation states with very different cultural outlooks and histories into the same mould, and it doesn't work. That's why you have the V4 grouping; that's why Italy is on the cusp.
You also have the issue that some of those who wish to come and settle in Europe can't cope with liberal values and prefer their own set of mores. Rather than conforming to European norms, they then import their own which don't chime with the laws in European countries, and cause problems.
I am against further expansion, and am especially worried about Serbia, especially given the reports from the State dept every year on trafficking.
'Serbia is a source, transit, and destination country for men, women, and children subjected to sex trafficking and forced labor, including domestic servitude and forced begging. Serbian women are subjected to sex trafficking both in Serbia and in neighboring countries and throughout Europe, particularly Austria, Germany, Turkey, and Italy. Serbian nationals, primarily men, are subjected to forced labor in labor-intensive sectors, such as the construction industry, in European countries (including Azerbaijan, Slovenia, and Russia) and the United Arab Emirates. Serbian children, particularly Roma, are subjected within the country to sex trafficking, forced labor, forced begging, and petty crime. Thousands of migrants and refugees from Afghanistan, Iraq, Syria, and neighboring countries transiting through or stranded in Serbia are vulnerable to trafficking within Serbia. Alleged traffickers reportedly influenced some trafficking cases through bribery of the victim or judge. '
Arms trafficking too: www.reuters.com/article/us-france-shooting-gunrunners-insight/gaffer-tape-and-500-euros-running-guns-to-the-heart-of-europe-idUSKBN0TH05420151128