Bush's Approval Ratings go into the tank:

Newsweek Poll: 45% Approval/48% disapproval (lowest Newsweek approval rating in his presidency, down 5% from 6 weeks ago)
Pew Research Center Poll: 45% Approval/46% Disapproval  (Down 5% since 2nd inauguration)
CBS Poll: 43% Approval/48% Disapproval (Down 6% from 3 weeks ago, ties for lowest CBS approval rating of his)
CNN/Gallup Poll: 45% approval/49% Disapproval (Down 7% from last week, and down 12% from 6 weeks ago, lowest of his Presidency)

Lets look at his approval ratings on individual issues (this will tell you why his overall rankings are taking):

(various polls are used)
Bush's handing of Iraq: 39% approve/53% disapprove (down 6% from last month)
Favor or Oppose War In Iraq: 47% favor/47% oppose
Bush handling of War on disapprove (down 2% from last month)
Bush handling of Social Security: 31% approve/58% disapprove (down 6% from 2 weeks back, and down 9% from a month ago)
Terrorism 52% approve/43% disapprove (down 5% from 2 weeks ago)
Bush Handling of Alaska Oil Drilling: 42% approve/46% disapprove
Bush handling of Schiavo case: 31% approve/56% disapprove
Bush handling of Economy: 36% approve/53%