[JeffF.]

The destruction of the ring was not an attempt on Sauron's life. As Gandalf describes at the Last Debate in RotK,"If he (Sauron) regains it (the ring)...his victory will be swift and complete, so complete that none can foresee the end of it while this world lasts. If it is destroyed than he will fall; and his fall will be so low that none can foresee his arising ever again. For he will lose the best part of his strength that was native to him in the beginning...and he will be maimed forever."

The attempt to destroy the ring was to render Sauron helpless rather than kill him.