So basically, you have noticed a major improvement in the Saudi armed forces in Operation Decisive Storm compared to Operation Scorched Earth in 2009-2010.

However, in 2009 the Saudis had the support of Saleh and most of the Yemeni military, whereas now they don’t. If I am reading you correctly, the Saudis are going to have to have a “come to Jesus” moment and negotiate with Saleh. Yet Saleh is divisive and excels more at playing spoiler and rendering Yemen ungovernable without his imprimatur, than he does at governing without unrest. But Riyadh will have to make hard choices and prioritize. Is confronting Saleh’s coup d’état worth Iran gaining a foothold on the Saudi-Yemeni border?

What would make Iran find the intervention in Syria costly? Obviously Johnson’s idea of cost differed from Minh’s in the 1960s…

As for Israel, I think it is satisfied that the Sunnis and Shias are killing each other and not fighting the Jewish State.