User blog comment:Fizzywizzy/Just to let you know.../@comment-1886172-20110317234533/@comment-1886172-20110318013122

He knew they would help the Americans as he knew certain places of DC would be EMP hardened. And from what Shepard said it was clear the US was losing due to being out aired and vehicled. The EMP shut down all vehicles giving the US a fighting chance. So knowing a nuke in low orbit would create an EMP he launched one with detonation coordinates of over the American east coast.