It looks certain that the attack on a Christmas market in Germany was an Islamist terror assault, and very likely that the attack on an Islamic prayer centre was carried out by a far right extremist.  Twelve people died in the former and three in the latter.  If the most likely explanation of yesterday’s killings holds, we see an image of what such groups as ISIS want in Europe, and neo-nazis too.  That’s to say, a religious war that is inextricably linked to ethnicity, with uncommitted Muslims and non-Muslims driven by mass slaughter to support and back extremists on either side.

The danger of being caught up here in a terror attack is small, and it is more likely to be an Islamist one – which faithfully mirrors the standing and firepower of the two ideologies worldwide.  The same applies in Switzerland and Germany.  But dry statistics don’t always determine human behaviour.  Britain has not seen an Islamist terror attack aimed at causing mass casualties since the assault on Glasgow airport in 2008.  We can comfort ourselves by saying that Britain’s Muslims are better integrated than Germany’s, but the harsh truth is that we have had some narrow shaves over the past near-decade.

Our security services have managed superbly, and we should all be grateful to them.  But a danger thwarted is not a danger ended – and no country is immune from being destablised by mass slaughter.  Germany’s democratic consensus is very strong, but yesterday’s atrocity will do Angela Merkel no good in the country’s coming elections, which are important for Britain in any event.  It is hard to see how talks on a post-Brexit trade deal can make much progress before we know what Germany’s next government will be.  That gives us about 18 months to agree one within the Article 50 timetable: hence the talk of an interim deal or interim arrangements.

German voters will be rocked by yesterday’s slaughter, and it is no coincidence that the perpetrator (or pepetrators if more than one person was involved) targeted a site associated with Christianity’s most popular festival.  Vladimir Putin, by contrast, is likely to take the murder of Russia’s ambassador in Turkey in his stride.  He and Erdogan have been creeping towards an accommodation.  No wonder that Russian politicians are already hinting that the West was responsible, and some Turkish ones are blaming the Gulen movement.  Terrror shakes democracies but leaves autocrats unstirred.