The region has only a modicum of oil wealth as the SDF has seized Syrian fields east of the Euphrates. Foreign subsidies will be necessary for many years or even decades. The Saudis and their Gulf allies may foot the bill, or large parts of it, but the US will be relied upon for arms, training, and air power. Washington will also be tasked with keeping the political system in working order -- another dubious and perhaps endless mission.
Creating Sunnistan will be a costly and lengthy undertaking that anchors the US in Syria for decades. It's difficult to discern any compelling national security interest in eastern Syria. American will not be stronger for the effort. The US economy will, however, benefit from Saudi arms sales. As noted earlier, no president can ignore that.
The House of Saud is well represented in the high councils of government. If commander-in-chief Eisenhower were around today, he might refer to a "military industrial-Saudi complex", perhaps angrily.
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