I thought vital Saudi installations were protected by the US

I was wrong. No one was watching no one saw anything. No one even knows from where the attackers came from and why.

P.S.: Two days after the attack, I can't find a declaration by Saudi authorities. Missing are the typical Arab war harangues swearing vengeance. Their silence is mystery.

Apparently no human was hurt, it was a surgical drone attack. Iran says they were not them. The Yemenis assumed responsibility but the attack came from the north and they are too far to target four (see pic) tanks with such precision. My take: Someone is trying to provoke a war against Iran, probably the Ayatollahs themselves.  From Kever Benjamin city, it looks like Iran understood that its efforts to attack Israel are met with strong resistance, while Saudi has no military resources. Its protector, the USA, wants to avoid war at all costs. Trump said: Iran is guilty but I don't want war. As if war was something one wants or does not want. Like in poker, pass (*).

The winter is coming and Europe needs heating oil.  Europe has even less desire to protect militarily the oil flow. Iran and other "rogues" have been saying for ages that the West has lost its mojo and is a "paper tiger". Now they seem to believe in it. Not good.

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(*)  What is a pass in poker? Pass - To refrain from calling or betting when it is your turn to act. To “pass" is to indicate that one is folding when facing a bet which don't intend to call.