That is an interesting angle. They have quite a nationalistic past and groups such as the IRA promoted it. It would be pretty strange to put up a wall to keep the Irish out while the Irish will be open to the import of millions of Europeans and soon 75,000,000 Turks. What a mess.
This is also pretty stupid if you step back a bit. The EU was originally formed and promoted as a trade facilitator. By lowering the trans-European barriers to trade, Europe could better compete with Asia and America. Interestingly, it was the EU that was used as a threat in the US to promote the passage of NAFTA (hear that sucking sound?). Now, 40 years later, national sovereignty is being threatened across Europe and hundreds of years of international relationships are being scrapped. Some of Hitler's goals to unite Europe into a centrally governed body, the suggestion by Junker to establish an EU army and the "effective" antisemitism of broad pro-Islamic policies are reappearing.
Like I said. What a mess!