The European Union is basically a trade agreement, with a few foreign policy rules thrown in. And the trade agreement is a good one: is outlines the bare minimum requirements to partake of the benefits of EU trade. It stops a member state selling out its environment and its people to undercut the European market. Corn from anywhere in the EU should be held to the same environmental standard, and services (like banking) from anywhere in the EU will be offered by workers afforded the same rights under the EU Work Time Directive, and other directives.
And the United Kingdom (UK) is apparently considering leaving it, all because of a few foreign policy rules. The EU mandates restriction-free travel across its member states. As an Island, Great Britain (and the wider UK) have already subverted that rule; you need a passport to come here, even from within the EU. But, one is also entitled to the benefits of the member state: welfare, healthcare and unemployment allowances; child benefits and an education. That, the UK argues, is an overly burdensome budget concern. (Which takes us to Schrodinger’s Migrant: both stealing your job and on benefits.)
But, what would the UK actually do outside of the EU? This short series is going to argue that either no one knows what the UK will do if it leaves the EU, which is akin to leaving a good thing for no particular thing at all, else the UK will have to quickly re-establish a relationship with Europe that will look almost exactly like the relationship it already has. Import taxes and trade agreements are defined by the EU, so the import tax paid on goods from, say, China in the UK are set by the EU. If the UK were to leave, it would need to negotiate a trade agreement with China, as the UK would not longer be apart of the EU agreements. The UK would also have to make a similar agreement with the USA, India and everyone else. And this is not a skill set we have; most of the UK’s international agreements have been done through the EU, using EU lawyers.
When I say the UK would have to negotiate a new trade agreement with everyone, I mean everyone, including the EU. The EU trade rules that bind the member states are designed to stop one state from undercutting the rest of Europe in a race to the bottom, environmentally and with human rights. The EU will probably not allow us to undercut their market in a workable system; to get an import tax on British goods that doesn’t cripple our economy, we are likely to still need to abide by EU rules. We’d be putting all our efforts to re-joining the EU, but without the democratic position we currently have.