Iraq: (temporary) success ?

The US military death toll in Iraq -- only one of several barometers of potential progress in the country -- has recently been in sharp decline. Yet without a sustained downward trend in the number of fatalities, it is too early to say that the United States has turned the corner in Iraq, as the graph below shows.

If the monthly US military deaths in Iraq are rendered as dots on a scatterplot -- a format favoured by statisticians when they want to show nonlinear relationships between variables -- the pattern shows a positive, albeit weak, correlation. US military deaths may have nosedived over the last couple of months, but there is an overall upwards trajectory in terms of the average number of fatalities per month. Any significant attack by insurgents in the next few weeks could quickly wipe out the downward trend.

The US military says violent attacks in Iraq have fallen 55% since nearly 30,000 additional troops arrived in the country by June, and some areas are experiencing their lowest levels of violence since the summer of 2005. This bears elaboration:

• Violent attacks have fallen from relatively high levels: 2007 was one of the most violent years in the war.
• 'Al-Qaida in Mesopotamia', a Sunni insurgent group considered to be the Washington's most ruthless enemy in Iraq, has been greatly weakened by US military attacks.
• Thousands of Sunni volunteers have recently joined the US effort, which has doubled the number of eyes and ears available to the military.
• Iran appears to be stanching the flow of roadside bombs into Iraq.
• Many Iraqis appear to be war-weary and eager for stability.

Given the failure of Iraqi leaders to achieve reconciliation, the recent downward trend in violence may not prove durable. It is likely that attack levels will fluctuate in the future: the graph illustrates that past periods of relative calm in Iraq have been shattered by sudden spikes in bloodletting. US officials have already complained that the Iraqi government is not taking the opportunity in the current lull in violence to attempt serious political progress.