I missed the McClatchy story about yesterday’s bomb attack against the bridge in Diyala. The military was caught flat-footed, but that’s not surprising. In counter-guerrilla warfare the established force is usually reacting to guerrilla movements.

BAGHDAD - In at least the seventh attack on Iraqi bridges in the past two months, a bomb damaged a bridge over a tributary to the Tigris River on Monday, cutting off the most popular route from the northeastern part of Diyala province to Baghdad.

With the al-Sabtiya Bridge no longer usable, people heading to Baghdad from Diyala will have to travel through the violent city of Baqouba, residents said. Baqouba is the scene of daily clashes between al-Qaida in Iraq insurgents, Shiite Muslim militias and Iraqi security forces.

Eyewitnesses said a truck loaded with explosives moved onto the span and its driver detonated his cargo, sending pieces of the bridge into the water below.

The U.S. military had no immediate information on the bombing, spokesman Lt. Col. Chris Garver said. Garver said bridge bombings didn't greatly "impede the mobility of the military." But bridges are high-profile targets whose destruction affects the lives of civilians, he said.

I’m not an expert on Iraq, nor a specialist in logistics, but I can accept LTC Garver’s statement that these bridge attacks don’t impede the military’s mobility. And I‘m sure that they can ship all the water, food, munitions, POL for vehicles, changes of clothing, new improved tactical vests, etc by air to troops needing resupply, because there are a lot of airfields scattered around Iraq.

Unless we go through another bout of falling helicopters.

If you compare the map I pointed out yesterday in comments [left column: “Map of Iraq”] with this map you’ll see that all US installations are very close to airfields.

Rather than an attempt to isolate US forces or impede their rapid reinforcement, LTC Garver sees the bridge campaign as an attempt to isolate the national government.

If there is a definite campaign against bridges this is an insurgency trying to destabilize the government," he said.

In the past two months, car bombs have targeted at least seven bridges. The attacks began in April with the destruction of the Sarafiya bridge in Baghdad, which connected the east and west banks of the capital.

On May 11, three vehicle bombs detonated on two bridges in south Baghdad and a busy thoroughfare that leads to Taji, north of the capital.

On June 2, bombs severely damaged a bridge that links a highway from Baghdad with the northern city of Kirkuk, forcing traffic headed to Baghdad to pass through Diyala province.

That would be very stable government that has daily bombings and thuggish executions daily on the streets of its capital and can’t secure major sections of the neighborhoods.

It is apparently a part of the official syllabus at the Army Command and Staff College that any military or guerrilla campaign can have only one goal.

Maybe second goals are merely pick-ups.