By Andrew North
BBC News, Baghdad
Trying to get into the centre of Baghdad earlier this week offered one view of how far away the Americans and Iraqi authorities are from gaining control here.
The US surge involves intelligence-led raids to track down militants
We were at the airport. Just before we were due to leave, the entrance car park was hit by a car bomb.
US troops and private security forces who guard the perimeter locked the whole area down for the next four hours. No traffic was allowed in or out.
While we waited with scores of other vehicles, mortars were fired at the airport. Fortunately for us they landed on the other side of the runway, plumes of smoke shooting into the air.
You won't have heard about any of this because at the same time a series of other far more serious attacks was taking place.
One was at the Sadriya market in the city centre, where a massive car bomb killed more than 140 people.
It was placed at the entrance to a set of barriers put up around another part of the market where a previous single bomb, in February, claimed more than 130 lives.
The market blast "did not penetrate the emplaced barriers" a later US military press release helpfully pointed out, ignoring the fact that the bombers had yet again adapted their tactics with vicious perfection - setting off their device at the point where crowds congregated outside and at the very moment when they were busiest.
As we drove into the city, we counted six blast holes left by recent roadside bombs along just one 100-metre stretch of road.
A large patch of damaged, blackened Tarmac on a bridge spoke of another attempt to destroy a key crossing.
The Sunni extremists held to be responsible for these attacks seem to be making a mockery of the US and Iraqi security plan, which is now into its third month.
So far, their surge seems to be having more effect than the American one.
Last month alone there were more than 100 car bombings, and the number of attacks has continued at a similar rate so far this month. This indicates a high level of organisation.
This despite the fact that there are many extra US and Iraqi troops in the city now. There are more raids and patrols.
On our drive into the city, we encountered several Iraqi army checkpoints. But almost every vehicle - including ours - was being waved through.
Many new checkpoints have been set up across Baghdad.
But what is their purpose, many Iraqis ask, when they seem to stop so few people?
It is not always encouraging when they do - a couple of times we have been pulled over by Iraqi soldiers who ask us if we have any bullets to give them.
Just a month ago there was a cautious - very cautious, but still real - sense of optimism among many Baghdadis that the plan was starting to work.
The daily count of bodies found around the city - mostly Sunni victims of targeted sectarian killings - had dropped off significantly.
The Shia militia of Moqtada Sadr, which was blamed for most of these murders, was largely obeying orders to put away its weapons and co-operate with the security plan.
But there is a deadly and familiar equation here.
Troops often come face to face with terrified and exasperated Iraqis
With official security forces apparently unable to protect Shia communities, pressure is growing on the militias to do so again.
And there are signs their death squads have returned to work. The body count is creeping up again. Twenty were found yesterday.
Dealing with the car bomb is "our top priority", says US military spokesman Lt Col Chris Garver.
But as ever it is a game of cat and mouse, played with insurgents who are "very adaptive", and very well-funded.
A man arrested by US soldiers after placing a truck bomb which failed to go off told interrogators he had been paid $30,000 (£15,000) for the task.
Lt Col Garver says the US believes it is up against several "car bombing networks".
"If there was just one, we might be able to pull the string and unravel it," he says.
People still have to be patient, he warns, adding a note of optimism.
"We are still not fully staffed," he says - there are another two months to go until all the extra US troops are in Baghdad.
But there is frustration too among the Americans at the Iraqi government's lack of progress on reconciliation - ultimately the only solution to the conflict, most believe.
Key issues include the need to implement a new law on sharing oil revenues, an amnesty programme and limiting the scope of the de-Baathification process. All of these are crucial to winning over Sunnis.
The idea was that the security drive in Baghdad would create "space" for such efforts to get going. But although new laws have been drafted they are a long way from being approved.
US Defence Secretary Robert Gates stepped up the pressure over these issues on his visit to Baghdad. In the meantime, the young men and women sent out here to implement President Bush's plan are paying a heavy price.
An average of 80-90 Americans die each month. And US personnel have just had their tours extended by another three months.
But, as it has always been since the 2003 invasion, it is the Iraqis who suffer most.
No-one knows the exact figures, but at the end of another week of unspeakable, random carnage, hundreds more Iraqi families are grieving.
Exhaustion and despair hang over the country.
And there are no signs of change.