A Slip of the Pen - New York Times
The issue of signing statements by the president is fascinating. At first thought, wouldn't it be better if the president just refused to sign a law he disagrees with? In this editorial Walter Dellinger gives examples of why a president may need to sign an omnibus bill which has a few provisions he doesn't approve.
The real problem here is the question of proportion. A president or Congress may need to do things that are, strictly speaking, illegal. The important thing is not to do it too often, only in cases of emergency. If the president would honestly reject bills he doesn't feel he can enforce, then the few cases of signing statements wouldn't be a problem. The system won't work if everyone insists on going past the boundaries every time.