Sure..they don't want the land.
They simply want to make us pull out of Iraq, the ME in general, etc.
A few well-placed nukes would accomplish the objective quite nicely. Kind of a "we have more. Now, want to reconsider?".
Let's hope they don't.
Plus- if they have targetted the DC-NY-Philly triangle with the nukes- maybe they hope that the prevailing winds will shift the fallout out to sea---and spare our agricultural areas....
I don't think they have any intention of wanting to inhabit our East Coast Cities.
Actually, in the context of all of this- one of the best places to visit might be Dearborn, Michigan ! :)