Depends on how you want to take out the central columns. The US has small demolition nuclear charges that would account for the extreme heat and melted steel found weeks later at the site.
As well as seismic shocks and elevated Tritium levels.
Special Atomic Demolition Munition (SADM)
In the 1950s and 1960s, the U.S. developed lightweight nuclear devices to use in the interest of U.S. national security. The Special Atomic Demolition Munition (SADM) was a Navy and Marines project that was demonstrated as feasible in the mid-to-late 1960s, but was never used. The project, which involved a small nuclear weapon, was designed to allow one individual to parachute from any type of aircraft carrying the weapon package that would be placed in a harbor or other strategic location that could be accessed from the sea. Another parachutist without a weapon package would follow the first parachutist to provide support as needed. The two-man team would place the weapon package in an acceptable location, set the timer, and swim out into the ocean where they would be retrieved by a submarine or other high-speed water craft. The parachute jumps and the retrieval procedures were practiced extensively. While the procedures were practiced extensively, SADM was never used. These types of weapons are no longer in the stockpile.
Mike - Please do some research for yourself.