Foreign investments are good. Especially when they inject our economy with capital, in trade for real estate, only to have to sell it back to us for pennies on the dollar (see the late 80s)
Foreign Oil is the problem. We need to re-open wells in the States & open new ones in the Gulf & Alaska.
Dubai presents another tangible asset to the US....Al Dhafra Air Base.
Take a look at
this map. I have no idea why the yellow line is there but it begins in or near the UAE. Take a look at the surrounding countries & ask yourself, what strategic help would the UAE be against, say, a soon-to-be (or wannabe) nuclear power. Especially if the part of the secret deal has other secrets (like unfettered air & port access)