The caliphate of the Islamic State existed for centuries

Just for what it's worth, the "caliphate" (or Muslim religious state) that ISIS or the Islam State would like to establish in Iraq and The Levant (Syria) is not something new, and it has been something the people of the region have desired since the fall of the Ottoman Empire after World War I.

The Ottoman Dynasty, which ruled the Ottoman Empire from 1299 until 1922 (source) was a Muslim Caliphate for most of its existence.  After World War I, the Arab lands that were part of the Ottoman Empire were divided into spheres of influence by the French and the British and that land (the Levant and Mesopotamia) became the artificial countries we know today as Syria, Iraq, Jordan and Lebanon (see the map below).  The modern Levant is confined to the state of Syria.

A caliphate is not something new that is being offered to the people of the region; it's something that is being returned to them, after having been taken away.  As the US-imposed dictatorships are being deposed; this is what fills the power void left behind.

What do the Sunni Arabs who live there desire?  Who cares, right?  It is being decided for them.

The United States spent a quarter century bombing, invading and occupying Iraq to rid itself of Saddam Hussein, and now can only dream of having such a strong secular leader in that broken region (no longer one nation), a leader who ruthlessly opposed the sort of religious extremism that has replaced his rule (and who was, by the way, a bitter enemy of al-Qaeda, which supports no secular Muslim rulers).