He still held a vote pen that he did not use.
A President, during a time of war, has a huge responsibility to keep the Country united. That would automatically limit the use of a veto pen. That, and after consulting with the GOP Senate (Snowe, Collins, Graham, Specter, McCain, Murkowski, Lugar, Bond, Hutchinson, Voinovich, Lott, etc. - with 'friends' like this, who needs enemies?), he realized he did not have a snowball's chance in Hades of ever having a veto upheld.
I assume you mean “veto” pen. Another lie. His first veto was to stop embryonic stem cell experiments.