BRUSSELS — The European Union launched an ambitious effort earlier this year to combat election interference: an early-warning system that would sound alarms about Russian propaganda. Despite high expectations, however, records show that the system has become a repository for a mishmash of information, produced no alerts and is already at risk of becoming defunct.

Indeed, even before the European Parliament elections this spring, an inside joke was circulating in Brussels about the Rapid Alert System: It’s not rapid. There are no alerts. And there’s no system.

Europe’s early struggles offer lessons for other nations, including the United States, where intelligence officials expect Russia to try to interfere in next year’s presidential election. In many ways, the European Union has been more aggressive than Washington in demanding changes from social media companies and seeking novel ways to fight disinformation.

But doing so has pushed the bloc into thorny areas where free speech, propaganda and national politics intersect. Efforts to identify and counter disinformation have proven not only deeply complicated, but also politically charged.