Yesterday's incident, during which Slovenian police arrested 59-year Croatian armed with five hand grenades at first looks just like an incident. An isolated incident, work of a troubled, disturbed, war-wounded mind whose alleged intentions - blowing up Slovenian prime minister Borut Pahor - should be described as nothing more than madness.
Media from both sides of the border are mostly trying to calm things down. Slovenia has economic interests in Croatia, as well as plenty of tourists on Croatian beaches. Croatia would also be ill-served by Slovenian-Croatian conflict escalating into spillage of blood.
Yet, this incident was something that simply waited to happen. You can't simply inflame chauvinism by blaming Slovenian neighbours for all the ills that have struck Croatia - including resignation of prime minister Ivo Sanader - and expect such chauvinism to stay in the realms of usually harmless ethnic jokes. Push anti-Slovenian line hard enough and there would be madmen ready to "solve" that problem with the same methods political problems were solved in 1990s.
Thankfully, no blood was spilled. But it could have been, and very easily. Josip Zagajski (the alleged terrorist in question) tried to set hand grenades off while being apprehended. If he died in subsequent explosion, he could have provided anti-Slovenian chauvinists with a martyr figure. If Slovenian policeman or policemen died, anti-Croatian chauvinists from the other side of the border would have new martyrs, while Croatia would be branded as a nation of lunatic terrorists, never worthy of EU entry.
This incident could be something of a waking call for politicians, or at least those more sensible on the both sides of the border. What looks like a petty little border dispute - or one of many topics in EU internal debates over enlargments - could easily escalate into something unimaginable. Just as some seemingly petty constitutional squabbles of late 1980s ended with mass graves being dug around Srebrenica.