The Balkans once again show that even the smallest thing can grow into a diplomatic drama. The trigger this time is an entry ban - allegedly, Montenegro barred entry to Dragan J. Vučićević, the editor-in-chief of a Serbian paper. And from Belgrade, according to sources, a "fierce and brutal" response is already being prepared, on the principle of reciprocity.

So far neither side has officially confirmed the ban - neither Podgorica nor Belgrade. But that hasn't stopped the retaliation machine from kicking in. According to sources close to Belgrade, the response would mean an entry ban for at least ten Montenegrin citizens, among them media editors and public figures. One ban pulls ten - that's the arithmetic of Balkan stubbornness.

Official Belgrade, it's said, sees such a decision as political, not administrative - and therefore demands a response "in equal measure." The translation is simple: this isn't about one man and one border, but about a message between two governments that are already on strained terms anyway.

And here comes the familiar Balkan question - who ends up paying for this one-upmanship? Not the editors and not the politicians, who turn bans into headlines and campaigns. But the ordinary people on both sides, for whom border crossings become one more reminder that neighbors raise walls more easily than they tear them down. How many times have we seen the same film already, just with different names?