It's complex because it keeps getting added to, so that it can pander to every lobbyist that drops a dime in a congress-critters pocket.

The lobbyist will NEVER go away.

http://www.nytimes.com/2011/03/25/bu...pagewanted=all

"General Electric, the nation’s largest corporation, had a very good year in 2010.

The company reported worldwide profits of $14.2 billion, and said $5.1 billion of the total came from its operations in the United States.
Its American tax bill? None. In fact, G.E. claimed a tax benefit of $3.2 billion"