In the north and west of Iraq Wednesday, troops were wrapping up operations designed to restore government control to insurgent dominated towns, in an effort to deny foreign and local insurgents the "rat-lines" to move men and equipment into Baghdad and other cities to carry out major attacks.
Meanwhile in Baghdad, at least a dozen explosions thundered across the city, with the deadliest a suicide attack that killed at least 114 laborers waiting for jobs in a Shiite neighborhood. In total, at least 152 were killed - the single largest one-day death toll attributed to insurgent attacks in Baghdad.
The contrast between what are being described as largely successful operations against insurgent hotbeds in Tal Afar, Qaim, and Haditha - towns with historic trading links to Syria that the US military says are way-stations for foreign fighters - and ongoing violence across the country, demonstrates the fluidity of Iraq's insurgency against thinly spread US and Iraqi forces.
In particular, the assault on the ethnic-Turkmen town of Tal Afar - where 8,500 US and Iraqi troops, largely drawn from the ethnic Kurdish peshmerga militia, took over the city this week - was aimed at limiting the mobility of Sunni insurgents. "It is a pathway from Syria that pretty historically was a trading route and smuggling route into Iraq," said US military spokesman Lt. Col. Steve Boylan.
An estimated 200 militants were killed and hundreds captured. But as forces moved on the city, the US military said many insurgents simply fled, using a network of tunnels they'd created in advance of the assault. That pattern has become increasingly common since the April assault on Fallujah, where hundreds of insurgents died in the most sustained combat of the war.
Instead of standing up to superior US firepower - particularly air support that drops 500-pound bombs on insurgent positions - insurgents now generally avoid major engagements. Instead of holding their ground, insurgents are counting on US forces to eventually withdraw and on the Iraqi forces left behind not being able to prevent their return.
So far, that approach has worked. This was at least the third major assault on Tal Afar in the past 18 months. As in previous engagements in western Iraqi towns along the Euphrates like Hit, Haditha, and Qaim, the insurgents reasserted themselves when US forces were shifted elsewhere.
Colonel Boylan says that while much of the US effort is focused on shutting off infiltration into Iraq, completely sealing Iraq off isn't likely. "To say it's shutdown is difficult. It's almost impossible to physically shut it down."
That's because of the topography of the desert and expanses of arid plains in along the 270-mile border with Syria, Boylan noted.
"The border is absolutely something you can't seal. I wandered back and forth across those borders in the region for a long, long time where there's supposed to be border guards and desert police, but you just don't see them,'' says Col. Pat Lang (ret.), a former head of Middle East intelligence analysis for the Pentagon's Defense Intelligence Agency.
Colonel Lang says that when the US masses troops, as in Tal Afar, it's always going to win, but that it doesn't have enough troops to deny insurgents sanctuary elsewhere, essentially shifting the problem around.
"The insurgents are increasingly creating redoubt areas, the kinds of places we can't go without stripping people from elsewhere and entering in large numbers,'' says Lang. "Therefore the insurgents own it 95 percent of the time. The object of the drill for the guerrillas is not to fight [US forces] head-to-head, but to wait until they have an advantage."
That's what happened in much of the Western portion of the Sunni-dominated Anbar province this year. In a major operation there last March, US Marines swept through Hit and other cities, and encountered little resistance as insurgents melted away. At the time, Marine commanders fretted about what would happen when they rotated out at the end of the month, and were replaced by other Marine units with about 1,000 fewer troops.
Officers and enlisted men at the time said they worried that their replacements would be in greater danger because of their smaller size. Roads wouldn't be patrolled as often to keep them clear of concealed bombs. At least 40 US troops have been killed in Western Anbar since the start of August.
And in Tal Afar, a city of 200,000 people, there are other concerns. The city's mostly Turkomen population views the Kurds as their ancestral enemies, so ethnic tension could be ratcheted up after using mostly Kurdish militias to attack the city.
Walid Sharika, a Turkman member of the national assembly and on a government committee focusing in Tal Afar, says that while he's glad the assault took place, ethnic divisions there have been widened.
"This should have happened four or five months ago because Tal Afar is one of the most important terrorism bases in all the world. I believe for a lot of problems in Iraq the source is Tal Afar," he says.
Even so, "more than half the city is destroyed and there are a lot of refugees living in a camp and we lost children and elderly," says Sharika.