In fact, starting right after 9/11 -- at the latest -- the goal has always been to create "regime change" and instability in Iraq, Iran, Syria, Libya, Sudan, Somalia and Lebanon so as to protect Israel. And the goal was never really to destroy Al Qaeda.
As reported in a new article in Asia Times:
Three weeks after the September 11, 2001, terror attacks, former US defense secretary Donald Rumsfeld established an official military objective of not only removing the Saddam Hussein regime by force but overturning the regime in Iran, as well as in Syria and four other countries in the Middle East, according to a document quoted extensively in then-under secretary of defense for policy Douglas Feith's recently published account of the Iraq war decisions. Feith's account further indicates that this aggressive aim of remaking the map of the Middle East by military force and the threat of force was supported explicitly by the country's top military leaders.
There is even more at George Washington's Blog