Your theory of preventive war is an excuse for aggression and expansion politics. You can always declare that some one wants to kill you while you are occupying his home and holding his family as hostages. Peace can be achieved in the Middle East very easy, when Israel acknowledges the right of the neighbours to live in their own state in the boarders of 1967.
U.S. to defend Syrian rebels with airpower, including from Assad (Reuters)
from the article: Olmert: Lebanon, damage to north take precedence