Absolutely, if you discount minor regional conflicts such as Word War II.

Even if you disregard that point, though, the overarching point of my comment still stands.

I'm starting to understand why the sentiments around EU here on HN is completely different from what I hear from anywhere else.

Ah, the famous European continent that includes only Western Europe. Approximately one million people died in the process of breaking up Yugoslavia.

Even if you disregard that point, though, the overarching point of my comment still stands.

The right wording might be "there were not yet a war between internationally recognized acting EU member states". That may still be an achievement, because you cannot say the same for a lot of other alliances, e. g. for NATO.