Every seventh-grade history student knows that the assassination of Archduke Franz Ferdinand of Austria in 1914 set off a chain of events that culminated in the outbreak of World War I. So what, in an increasingly fractious European bloc, is portended by last week’s attempted assassination of the Slovak prime minister, Robert Fico?

Like Ferdinand, Mr. Fico is a relatively obscure figure who is nevertheless at the heart of a central Europe where several social and political faultlines — populist right, progressive left, Russia versus West — are entangled. Like the heir presumptive to the Austro-Hungarian throne, the populist Slovak leader has been catapulted to the front pages by unforeseen, violent circumstances. 

The 59-year-old Mr. Fico, a former communist who acceded to power last year and has assumed a mantle of left-wing populism, was shot multiple times. Despite a shaky early prognosis he is reportedly on the mend. Yet a new iteration of the old Black Hand may be at work — and in the wake of the attempted killing,  threats on other European leaders have multiplied.

The day after the attempted hit on Mr. Fico, Prime Minister de Croo of Belgium filed a police complaint against a radio presenter who “called for the prime minister to be shot.” Mr. de Croo is one of the few European leaders who last month condemned a Brussels municipal official’s attempt to shut down a conservative political conference at which Nigel Farage of Brexit fame and the Hungarian leader, Viktor Orbán, were keynote speakers. 

Mr. Orbán has received threats on his life following the attack on Mr. Fico. So too has the Polish prime minister, Donald Tusk, albeit in a vague social media kind of way: Mr. Tusk posted to X a comment from a social media user that read in part, “The Slovaks have given us an example of what to do with Donald Tusk if he fails on the CPK.” The CPK is a major Polish transportation infrastructure project.

Other leaders, other threats: The Serbian president, Aleksandar Vučić, has received them, as has the president of the Serb Republic in Bosnia and Herzegovina, Milorad Dodi, and the prime minister of Kosovo, Albin Kurti. Reactions to the assassination attempt on the Slovak prime minister, in the meantime, have been swift and condemnation nearly unanimous.

According to Britain’s Sky News, the four (or by some reports five) rounds fired at Mr. Fico while he was greeting a crowd could have something to do with the politician’s well-known antipathy toward facilitating arms deliveries to Ukraine. Notable among the first leaders to offer moral support were Messrs. Vučić and Orbán — they even  promised to pay a joint visit to Mr. Fico in the hospital.

Like Mr. Fico, Messrs Vučić and Orbán are no great friends of Kyiv, and along with Poland and Hungary, Slovakia voted against a controversial recent European Union migration pact. There is little information about the would-be assassin, but according to unconfirmed media reports he was a 71-year-old retiree known as an amateur poet who may have once worked as a mall security guard. 

Government authorities, the AP reports, say the suspect didn’t belong to any political groups, but called the attack itself politically motivated. That characterization underscores the political frictions in Europe ahead of parliamentary elections in which 400 million Europeans will elect 720 lawmakers in the European Parliament. 

The Continent may not be as politically divided as America, where threats against public officials are also on the rise. Yet a sense of Europe’s  environment was to be had at last month’s Maastricht Debate, where the current president of the European Commission, Ursula von der Leyen, could barely bring herself to look the Identity and Democracy candidate, Anders Vistisen, in the eye. 

Such hostility to those with openly conservative views on a range of issues tends to telegraph that opposing views are not to be debated — and in that muddle the spasms of old European emities lurk. On the surface it may appear to be just about Slovakia, but the neo-liberal flank’s framing of anything to its immediate right as “populist” is now posing fresh dangers for an entire political class.