Sarumon and Sauron's War

[engwaalphiel]

i doubt that Saruman would . Even though Sauron had no body as such he was bound to the ring , and as we know that ring was one powerful thing ! There were many more Orcs under Sauron than Saruman and he had many more allies on his side (the Nazgul for instance).
The Uruk Hai were a newer race and would take a long time to get to an army large enough to defeat ME . Also just look at where they were residing at the times . Saruman in the sturdy but soon wrecked by the Ents , Orthanc or Sauron in the dark fortress of Barad Dur which are guarded by more than just orcs .

you do simply not walk into Mordor

Sauron had his own lands (well he thought he did) and a reputation at that.