Technically speaking, you're still incorrect. Algerian War happened inside the ECSC borders, however outside the European continent. Then, there were much smaller Basques-Spain and IRA-England conflicts.
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.
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.