Replace the rubble of the WTC with a memorial park, then burn down the UN building and make that into a memorial park as well.
Burn it down? How about a fuel air explosive bombs guided into several windows, then follow up with 2000 lb Laser Guided Bombs, two to four should do the job. Record and sell the videos. I'd pay good money to see that, real good. Put the money into the military, both that from sales and rental of the videos, and from that which we would have spent on UN dues and other indirect taxes.