The History of Executive Privilege

There is no question that George Bush has expanded the powers and
privileges of the executive branch more than any president in history.
Everything from signing statements to downright secrecy, Bush seems to
have given himself a permanent get-out-of-jail-free card. I guess you
gotta hand it to him: for someone so hell-bent on gutting the
constitution, he's been quite a success.

Here is an essay about the history of executive privilege
since WW II and how Republican presidents in particular have used
various tragedies (i.e. 9/11) to expand the powers of their office.