And the president can veto it.
As mentioned earlier upthread, September 11 changed everything and the number one priority of the Bush administration was the global war on terror and the defense of the country. He determined that he had to choose his battles with the Dems strategically.
"For the record, every alternative budget offered by the Democrats during the Bush years called for more spending and higher taxes than the President's budget." ... Rove: Courage and Consequence, page 237.