The UK and the EU are close to embarking on a trade war over The Protocol, which might even turn into violence in Northern Ireland and restart the Troubles. What? Are you mad? Possibly. So what is this Protocol? I wish I knew. The simplest explanation (which explains almost nothing) is that it is the barely comprehensible decree that for tariff purposes treats Northern Ireland as commercially part of the EU while the rest of the UK, that is, the island of Britain, remains outside it. Is that worth a war? I didn’t say it was. But it’s a reminder…