"From this point on boundaries are constantly shifting, with the Iraqi government’s control extending only a little beyond the side of the road, and sometimes not even there.
The 75-mile drive from Baghdad to Samarra plunges the traveler into Iraq’s precarious new reality. It is a world of Shiite militias, where many of the men carrying arms on behalf of the government have only the most tenuous ties to the Iraqi security forces.
And it is a world where Sunni militants, who advanced to within 50 miles of Baghdad in their initial burst last month before their drive stalled, often are no more than a mile or so away.
Travelers must read signs that would be invisible to a newcomer: Flags and uniforms signal safety or danger." NY Times
Beyond Samarra on the road to the north, the government's control must be even more precarious. Tikrit is a long way farther from Baghdad than Samarra under these conditions.
This means that the government force flailing about at Tikrit sits up there at the end of a long, pencil like line of supply that probably does not include much beyond the road itself and its shoulders.
I have been in many places like this in the Middle East and Central Asia. Frequently the actual extent of government control is limited to roads, checkpoints and towns at least nominally and partially in government hands. The authors are correct in saying that in these circumstances one must read the "signs" carefully, look at the people with guns, listen to what they do not want to tell you about their enemy's presence in the area. If you do not do that you will blunder into a zone of death.
The Arab historiographer Ibn Khaldun wrote long ago that political life in Muslim countries is like this because there are no traditions of political compromise and each group believes itself to be the sole practitioners of virtue.
The fact that the rebel coalition has not yet made a serious effort to cut that long, snakelike line of supply indicates to me that they are presently engaged in consolidation of their gains. pl