None of them actually *have* to. They choose to tolerate them as result of cultural differences, misconceptions and for business profits. They also most likely have intelligence indicating these are unsubstantiated threats. But even if they are unsubstantiated, lack of reaction creates an atmosphere of impunity and undermines trust in EU.
@kravietz 'dirty bombs' are an impractical threat anyway, unless you can get your hands on the good stuff (short-lived isotopes), they're unlikely to kill people very quickly.
But Lukashenka also kills dissidents in other European countries.
I get the impression that current Russian political culture values this sort of 'hard man'-posturing far more than European culture does, and it's hard for our leaders to understand and deal with.
@kravietz European leaders have to tolerate this kind of behavior from Putin. It's unclear to me why European leaders also accept this from his lap dog.