Re: @Tom Paine
That is a good point. But the way I rationalise it is by considering the on-going employability of people in the UK.
All the time that tax, benefits, health and other infrastructure services, education etc. are funded within an 'arbitrary regional border', I believe that pay and skills should also come mainly from within that arbitrary border.
If it were the case that full movement allowed people at the lower end of the demographic spectrum to get worthwhile jobs in other countries, then it would be great. But what is happening, and will continue to happen, is that people move from poorer countries to richer ones, displacing the lower skilled locals from the workforce because they are prepared to work for lower wages than the locals.
This occurs in two ways. One is the obvious one where locals just don't find work because it's being done by people who are prepared to work for less. The second, and much more subtle one, is that businesses in the UK don't bother training people from the UK. They just bring them in from abroad, saving themselves all of the costs of training.
What this leads to is a de-skilling of the local workforce, and perpetuates the situation that businesses can't recruit skills from the local workforce, and then bring even more people in from abroad. It will become a self perpetuating issue, whilst all the time money could well be leached from the UK economy.
But it is not just the UK that is harmed. If you look at countries like Poland, Hungary and even Ireland, such a large number of their young people who have got skills marketable in richer countries leave that they are starving their own countries of the skills they need!
I saw a documentary on Ireland that stated some villages effectively don't have any residents between the ages of 18 and 30, because they've all gone somewhere else to find work.
I would love to see a totally egalitarian world, where the resources of the world are equally shared, but we are so far away from that, with no possibility of ever getting there without some world-changing event, that we cannot afford to consider it.
It's absolutely pointless having a country with a 'healthy' economy for the shareholders and owners of the companies, if the rest of the population is un-employed, un-employable, or are effectively wage-slaves of the rich.