To learn from the mistakes of others you have to have a certain amount of humility and see yourself as the same as them and vulnerable in the same way as them, for instance if you live in the North America and you notice some other country slid into war or did something that didn't work, in order to learn from their mistake you have to think that you and your culture and people are just like them and you can have your society fall apart too. If you think that you are better, you won't be able to learn from or avoid their mistakes. Why would you learn from their mistakes ? You think you are invulnerable.

Also in a sense it helps if you just think the fact that you haven't yet made the mistakes of others or had those same bad consequences happen to you, you think that you simply had better luck or a better starting place, rather than taking credit for your success or relative success as a society.

But you have to think that you are human just like them.

Or for instance to learn from the mistakes of Nazi Germany, you have to have some sense of your fallibility and vulnerability as a human. You can't keep thinking "My country is better than that" or "Humanity is better than that now, we have better safeguards in place."