Pentagon

The Pentagon is a building that houses the center of power for the military of the United States of America. It is named so because of its pentagon shape.

Puppet Master imagined destroying the Pentagon along with the White House and United Nations building as part of his taking over the world.

When Thaddeus Ross attacked Stark Enterprises and Iron Man and War Machine stopped the Hulkbusters, Iron Man told Ross that Tony Stark would be sending a bill for the damages to the Pentagon.