Why would they? Iran has been fairly harmless for decades, and the downsides of starting a war with Iran are pretty obvious. What's next, starting a war with Egypt or Panama, just for funsies?

Pre-Trump, some European countries might've let themselves be dragged into another one of America's pointless unwinnable no-reason wars. But with America itself all but declaring war on its European "allies"? Not a chance. Unless Iran starts sending rockets to Europe (and why would they?), they'll just stay out of it and let America clean up its own mess.

If anything, the Ukraine situation has made Europe more pro-war, with countries significantly increasing their defense budgets. If Iran had been a "post-9/11 Afghanistan invasion" scenario under another President, 2026 Europe would happily jump in to help.