If you believe one man blew up the Murtagh building, I don't know what to say.
If you believe one man killed a President, you must be talking about President Garfield, although I'd blame that one on incompetent medical care and morbid obesity more than Giteau's bullet.
But I suppose you also believe that 19 Muslim hijackers crashed four airplanes on September 11th 2001, causing the collapse of two buildings in New York City.