Don't be silly. Carnivore was in use for YEARS before the Patriot Act was even put on paper. President Bush and Congress only want the court order because they want to set good precedents for future government behavior. Just with packet radio alone I can conclusively show that both government and private machines have a right to listen in on all data traffic, and that's merely a layman's example.
Or he simply has somewhat more repect for the Constitution than whoever set up Carnivore.