Well it's pretty simple to understand that Israel is supported by many western countries, and there are many others who do not support Israel and/or those western countries. Those western countries will support Israel and push their influence onto them, so anyone who wants to oppose the influence of either Israel or any of those western countries will have an incentive to support Iran in the conflict. What you have there is the same set of conditions that led to the world's previous global conflicts.
Well it's pretty simple to understand that Israel is supported by many western countries, and there are many others who do not support Israel and/or those western countries. Those western countries will support Israel and push their influence onto them, so anyone who wants to oppose the influence of either Israel or any of those western countries will have an incentive to support Iran in the conflict. What you have there is the same set of conditions that led to the world's previous global conflicts.