Italy has already elected a far right government that endorses fascist rallies
https://www.lemonde.fr/en/international/article/2024/01/10/italy-s-government-under-fire-from-opposition-after-fascist-rally-in-rome_6420540_4.html
AfD is making record gains in Germany
https://www.reuters.com/world/europe/germanys-far-right-makes-strong-gains-eu-vote-despite-scandals-2024-06-09/
National Rally are poised to win elections in France
https://www.bbc.com/news/live/world-europe-69102843
More of a german/french phenomenon than broadly european (though maybe france and germany are the only countries that really matter honestly), in most EU countries the further right wing parties are also pro-war, and here in portugal where the communist party has been consistently anti-war, moreso than dem soc Left Block, including opposing arms shipments to ukraine even, we just get consistently attacked and mischaracterized in the media and I can't say we've made electoral gains from taking a principled anti-nato position, maybe we will in the long run but not yet, it has definitely cost us votes.
Public opinion on the war hasn't soured that much here (fucking portuguese provincialism wanting to be "close to europe"), and even where it has a lot of people are still unwilling to go along with us when we call for something like a political solution.
I think the fact that France and Germany play such a dominant role in Europe is precisely why this is such a big problem.