Few of the world’s really awful events have been unexpected. For ten years before both the first and the second World Wars people were warning that something dreadful was about to happen. They might not have known what form exactly the catastrophe would take, though in both these cases European war was the obvious one. The atmosphere was febrile, culturally as well as politically. So neither war took many people by surprise.

Having intensively studied the history of those two periods, I think I can detect some of these same signs today. It’s not something I can back up with solid evidence, exactly; just a feeling I get from having soaked myself in the pre-1914 and pre-1939 periods. But there are things one can point to, common to all three times: and, significantly, not to others, or not in quite the same way. A recent economic depression is one, followed by stagnation. A widespread lack of confidence in both the economic and the political systems one is bound by is another. Pessimism was rife. Who is an optimist today? Growing nationalism almost everywhere is a third sign, much of it based quite manifestly on feelings of recent national humiliation. The rise of blatant irrationalism is a fourth, seen today most obviously in Donald Trump, but also, more mildly, in Michael Gove’s recent comment on ‘experts’. (And if you think I’m being patronizing there, it’s probably because you’re one of the irrationalists yourself. There are some around, even in academia.) There were some particularly ‘toxic’ political controversies before both wars, and on similar themes to today’s. A sixth sign may be the two substantial influxes of refugees that took place prior to the wars, in those cases both Jewish, unsettling communities, at the very least. There may be other parallels – moral shifts, criminal trends, literature (like dystopian science fiction), and artistic fashions – which I don’t know about, not having studied them deeply. But these will do for a start.

Lastly: there is the outpouring of published statements of doom and gloom coming out just now, as they did then, in a way that hasn’t been seen before in my lifetime – save from paranoid Tories under Labour (‘country’s going to the dogs…’), and of course at the time of the USA-USSR nuclear face-off. But this is different. Here’s one example, picked at random, posted by Owen Jones on Facebook at the height of the current poisonous debate over Brexit, and just after Jo Cox’s murder. ‘I love this country, but never have I been so scared about it. The growing bitterness, resentment and hatred is genuinely frightening.’ That’s typical. I go along with it.

Like most of the Cassandras before World Wars I and II, I’m not sure what guise the crisis will assume. I can see, or sense, the glowering clouds, but can’t tell what exactly they forebode. It’s unlikely to be another Anglo-German war – I guess. The best case scenario is a collapse of the government here, which might not be so bad. Ditto the break-up of the European Union. The worst case doesn’t bear thinking about, with the Donald’s finger on the nuclear button. But whichever it is, we can’t say we haven’t been warned.