During British rule of the Middle East, why weren't there considerations of carving out a separate Kurdish nation (ie from areas of Iraq and Syria especially)? I understand they had no control of Kurds in Turkey, but in the Arab lands they could have created one. Those people (Kurds) are a significant minority in all these countries. In Iran, they are also numerous, but the Persians are a kin to them (linguistic).
Politics and the law of diminishing returns. It's more expedient in many ways to deal with fewer people/factions, especially when the current regime is in one's pocket. This was the case under British rule, and was the same when the US had influence during the Iran-Iraq war. The US was supporting Iraq, so why rock the boat by supporting Kurds? Fairness has no place in politics.