I hate how “anti-war” has been hijacked by these people to mean, let imperialist countries invade whoever they want with no consequences. (in the case of tankies, any imperialist country that isn’t in NATO).
Remember that the original Canadian intent of the UN Peacekeepers was that they would forcibly create and enforce peace.
It was the USSR and the USA that objected to the concept.
Ireland has peacekeepers between Israel and Lebanon right now. They wouldn’t be there if “create peace” was one of the missions.
Peace must exist, however briefly, and then the peacekeepers place themselves in harm’s way to keep the peace.
Extend the mission to militarily “create peace” and suddenly you are just NATO/USA. How can either side trust a peace that was enforced upon them and not call it a defeat, whose borders are disputed for eternity? Every nationalist who wants to stir sentiment can just say “look what the British/Americans/UN imposed on us”. Outside forces drawing borders is pretty much the cause of 90% of warfare, civil and otherwise, for the last 80 years.
Similarly if most countries have a mutual defence pact, no one country will be able to invade another without being at war with literally the whole world.
I’m afraid that mutual defense isn’t as iron clad as you think. If Article 5 of NATO ever gets triggered you’ll get a masterclass on weaseling out of obligations. It’s ironic because Ukraine may already be receiving the kind of support a full NATO member is entitled to.
It only works if you actually commit to it.
But imagine the implications if a country did not commit to it (bar an obvious one like Hungary or Turkey). They’ll likely get sanctioned, probably will have trouble entering any useful alliances for the next decade or so because no one trusts them anymore.
Unfortunately with Trump the US will try to weasel their way out. Europe knows too well what happens.