“It is almost a law of nature that neighboring nations must hate each other, having to compete for the same living-space and other resources.”
Yes it is. Men are fallen and human creations are fallible.
It follows that border disputes and wars etc. are inevitable. And instead of trying to stop all wars, which is impossible, the effort should be to minimized their size and spread.
Gigantic alliances do the opposite. They ensure that the inevitable war will be gigantic when it comes.
I absolutely agree with you, on all three counts 👍