You're right. Alliances did shift since nations tend to look out for their best interest. But I was thinking more about the beginnings of conflicts. Alliances were often kept at that time, unless it was likely that one's ally would fall. They are made, most often, because one or both countries believe that they will have a better chance of winning a war allied with the other.
Even in cases where defeat seems likely there are cases of allies staying true. Much of Rome's Italian allies did not defect while Hannibal was destroying the countryside nearly unhindered. I don't know if they expected Rome to win in the end, but the situation was pretty bleak for some time. Perhaps a form of Italian nationalism was starting to take place. Still, we are both making generalizations. I concede that alliances could shift and be broken, but believe that they often were not at the beginning of the conflict.
Perhaps you read part of what I wrote on Carthage and Rome wrong. I did not say they stalemated each other nor did I mean to imply it. I understood that Rome won all the Punic Wars. Forgot about the 3rd one. My mistake.
I stand corrected about wars often being started at the start of a new season or after only a few years. I made a generalization that is not accurate. The situation is more variable, but I do believe that some countries were almost preordained to start fighting again, either because they hated each other or for more logical reason: economics, politics, etc.
Mad Scandinavian
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