The Post-Apocalyptic Roadmap/Washington

Part of the Post-Apocalyptic Roadmap Project.

Seattle gets nuked. But the warhead doesn't go off untill after its plunged into the river and detonates, nearly harmlessly, underground. The radiation kills off the surrounding suburbs, but leaving the cities mostly intact. The space needle is first inhabited by a humanitarian effort, hoping to bring the local radiation down to a habitable level. Their plans crumble as a mad scientist guns down the effort and uses their research to turn the Space Needle into a giant, radioactive death ray.

Most of the world never notices, because its fucking Seattle...