There's also a long history of tragic events happening precisely because everyone was preparing for them (see: WWI) and of course, of horribly wrong choices getting prepared for things that never happened.
WW1 wasn’t “started by preparation”. In fact it was the continuation of about 100 years of war, and the war continued for nearly 100 years afterward. Europe had been at war nearly continuously from Napoleon to 2000 .
The partition of Europe between the two victors of WW2 (USA and USSR) was part of the peace, not a state of war. The cold war wasn't a war inside Europe but between two rival superpowers; the Yugoslavia war wasn't one between EU countries but a civil war result of a change in external conditions.
And Stalin continued to take territory even later, moving into East Germany, Czechoslovakia, etc . Continuing with military pressure over the later years.
... and an equally long history of people "avoiding war", while refusing to be reasonable, right up to the point that a gigantic war becomes unavoidable. People will choose to go to war over a prolonged economic crisis. Such a crisis can easily be avoided by countries working together rather than push costs onto each other, but in any actual crisis they never do cooperate.
And of course, WWII would be an example of that. It was also far worse than WWI, including for Ireland. So there's even a very strong case that this is a self-destructive attitude for Ireland.
But if history teaches us anything, whether the example of the Weimar republic or anything else, it's that you can tell people this all you want. You can show how bad things are and how the situation cannot continue, people will NEVER accept what needs to be done, if it has to be done by them.
For example, right now it's pretty damn obvious European shared military presence in the East Sea and in Eastern European countries is a very desirable thing indeed. Every other EU country, and several others like Switzerland, have committed to put forward about 5% of GDP towards this (>10% of their total government budget) ... so it would seem only fair Ireland joins them, after all, without that presence Ireland's economy cannot keep working, because it cannot export or import freely. Ireland is letting other people pay for its safety, giving nothing in return, but Ireland is competing with them for the rewards of that safety. And your very comment shows that you're arguing to not do it, illustrating the problem. Of course, profiting economically of other countries while abandoning them militarily is exactly why Russia (and even China) think they can just conquer them. If that happens, it would be a total disaster for Ireland. But nobody cares.
And of course, Ireland is not currently in an economic crisis, quite the opposite, and could easily cooperate ... but doesn't. We can only imagine what will happen when inevitably, a crisis does come.
In fact Ireland currently has tax laws that let it essentially tax all of Europe (letting the FANG companies take profits out of Europe tax-free in return for jobs in Ireland, that are then heavily taxed by the Irish government. The employees of those companies are heavily taxed, btw, NOT the companies themselves). That's what the current Irish government actually prides itself on. Stealing tax revenue from it's main allies. Seriously.
So just so we're clear: Ireland is destroying corporate tax income in 30 EU countries, in trade for jobs, not filled by Irish people, in Dublin, so those can be taxed at >50%. This is, by the way, what the Irish government prides itself on, and it is why living in Dublin has basically become impossibly expensive.
It is also forcing the EU tax system to become 10x more complicated than it already is (the EU is working to have multinationals pay taxes in the countries where they make money, so any advantage of having a tax domicile in a specific country disappears. But of course, this will be complicated, to put it mildly)
