For a tactician, that's the easy part.

Nord, in Northeast Greenland, and/or perhaps a Scandinavian site, including Norway's Svalbard Island, would work. In those locations, though, the environment would be harsh for humans and machines alike, but still expensively doable.

From the immediate south, we have Ankara, situated in a fairly reputable NATO nation, but doubtless expensive to setup a strike-force staging area. Bulgaria, Armenia, Hungary and Romania might be coerced into assisting the mighty West, but who knows? All these have somewhat large Muslim communities, and the security of those regions might come into question.

...But there are really so many other points from which to choose, including northern Greece, or just stepping back into Iraq, and perhaps taking down Syria.

The tough part is economics and politics, where civilian and government backing, from the US, as well as the host nation's/nations' populations would be required.

I'm also leaving everything on the table, including nuclear force.

...And, as a powerful nation, we are already perceived to be arrogant, whether individually we are or are not. When visiting any nation, for any reason, it is up to the individual American to prove himself to be beautiful, or at least not ugly, and many times over. Of course, having this blessed ability is yet another sign of arrogance.