different situation - Arlington was meant to be a cemetary from its inception. If you turn ground zero into a cemetary, the terrorists have won. Those who died at ground zero are already memoralized in a cemetary elsewhere of their families choosing.
I agree with taking every REASONABLE measure to recover the human remains, then move on. The important part of everyone who died there is elsewhere (either heaven or hell), and recovering other bits of tissue will not change that.
I do not mean to sound calloused, I would say the same if I had family members killed at ground zero. We need to move on, but never forget.
Actually, it was meant to be the Custis family home -- Robert E. Lee married into the family, and came to own the estate. Arlington National Cemetery is where it is because the Union government basically decided to bury their dead in Lee's front yard, to insure that he'd never want to come back to his old home on a hilltop, where he could look across the river and see the Capitol on a clear day.
Arlington was for decades a family home; Gen. Meigs turned its front yard into a cemetery to make sure the home's owners - the Lees - could never live there again.