I tend to see myself as an agnostic on the European Union. I’m not a particular fan of anything about it, though I think it does have its qualities. Stopping politicians from throwing up barriers to migration and effectively banning them from renationalizing private industries are both good things, however undemocratic they may be. And I tend to think of the EU as being a force for good for Europe in general, the disastrous euro project notwithstanding. Of course there are huge problems with it as well. It is opaque, difficult to hold accountable and seems to hand down endless new regulations on everything from permitted working hours to olive oil storage. Britain’s legal and political institutions have evolved (and I stress the word evolved) quite separately from most of continental Europe’s, making it perhaps a poor fit with the rest of Europe. And, fundamentally, the EU is one extra layer of government, adding bureaucratic and political inertia to an already sclerotic political process.

But, as an agnostic, I am finding myself baffled and underwhelmed by the arguments currently being floated by “Leave” campaigners. So far, virtually none of them stand up to scrutiny. Unless something changes, I cannot see how these arguments can fly in a proper referendum.

Benefits: The issue of the day, thanks to a row between David Cameron and Donald Tusk that seems to be political theatre. The irrelevance of this was shown (by accident) by Julia Hartley-Brewer in a pro-Brexit piece today:

the argument often given by EU supporters is that very few migrants actually claim these benefits anyway, so it doesn’t really matter. According to the Government’s own figures, EU migrants on “in-work” benefits cost the taxpayer £530m in 2013. Total Government spending is £733 billion this year. While half a billion quid is not a small number to ordinary taxpayers, it is the principle that matters to most of us. Why should anyone be entitled to come to live in this country and claim welfare benefits without having first made any contribution?

Got that? The £530 million (0.07% of the budget) that we spend on tax credits for Europeans – less than we give to the Arts Council England every year (including Lotto funds) – is a ‘principled’ reason to leave the EU. Never mind that by any decent measure EU immigrants are net contributors to the budget in other respects, or that British citizens receive reciprocal benefits when they work abroad, I suppose. If this is the principle over which we should decide whether to stay or go, count me In.

The balance sheet: Vote Leave say we should stop spending £350 million a week (£18.2bn/year) to Brussels so we can spend that on the NHS or on science fuding.

Well, maybe. Firstly, that number appears to be misleading – it’s a gross figure and doesn’t include the UK’s rebate or other EU grants. When you do include those things, it falls to about £9bn a year. And, as (pro-Brexit) Pete North points out, quite a bit of the remaining money goes on projects we’d want to be involved in whether we were in or out, like Europol and Single European Sky, which coordinates airspace across Europe.

Yes, it also includes disgraces like the Common Agricultural Policy. But it’s hard to believe that any government would have the spine not to just subsidize farmers domestically if we left the EU. And our net contribution to the CAP is quite small anyway – almost as little as we spend on tax credits for Europeans.

Regulation: It’s not difficult to find annoying, wasteful, illiberal regulations that come from the EU. But the question is the counterfactual: if we were out, what would we have instead?

Practically everyone agrees that we’d want, and probably get, a free trade agreement with the EU if we left. But tariffs are not the main barriers to trade between developed nations. The TTIP negotiations underline that – only 10% of the projected benefits will come from abolishing tariffs between the EU and the US. The rest will come from removing regulatory barriers, whether through mutual recognition (we accept US regulations, they accept our regulations) or harmonization. Mutual recognition is preferable, but obviously is only politically viable if each set of regulations is roughly as harmful as the other. If not, one side of the agreement will be outdone on everything by its freer rival.

So what should we expect a UK-EU free trade agreement? At best we can hope for a situation where only British exporters (and their suppliers?) are bound by EU rules; at worst, one where we end up with exactly the same set of rules, only now without any say in how those rules are made. Arguably, these rules are not even really designed at EU level at all.

But even if we get the better end of that stick, who has confidence that a Britain freed from the EU would actually be particularly free market? Maybe we’d lose things like the Working Time Directive, but in the grand scheme of things is there any reason to expect this or any likely alternative government to be any less interventionist than Brussels is? Remember the Red Tape Challenge, or the ‘bonfire of the quangos’ that never was. The counterfactual is just not very encouraging.

The big picture: Perhaps the question is, as Madsen and the pseudonymous WhiteWednesday both say, not about the details at all. They say that it doesn't matter what the reforms secured now are: being in the EU means an inevitable drift towards further centralization and federalism. And the fact on regulation that little would change immediately is a feature of Brexit, not a bug – it takes the risk out of it, and makes reform a long-term project that we can approach on a case-by-case basis, not as the sort of all-or-nothing deal that some others are telling us is on the table.

Perhaps. This does seem to assume a certain degree of inevitability in the European project that is at odds with the idea that the EU, not just the Eurozone, is ready to collapse at any moment. I’m not so sure, and against this I must weigh the possibility that our immigration policy would become a lot more restrictive. For now, the arguments being made by the Leave campaigns just do not cut it.