Analysis: Iraq’s never-ending security crisis
In any other country, the detonation of 15 car bombs in a capital city on Monday and the dozens of resultant deaths would have been an unprecedented event.
But in Iraq, it was fairly unremarkable - the 38th such "spectacular" in the last 12 months.
As the country enters its 10th year in a state of deep security crisis, it is worth exploring the factors that sustain the conflict and the violent actors who frustrate the daily efforts of the Iraqi security forces.Al-Qaeda acceleration
To start with, Iraq is arguably experiencing two separate but interwoven security crises.
Experts differentiate between the "al-Qaeda stream" of mass-casualty attacks and what might be called a "normal insurgency" undertaken by local-level Sunni and Shia militant cells.
The international media pays most attention to the former because co-ordinated, multiple location car bombings are highly visible - as al-Qaeda's local affiliates intend them to be.
And the incidence of spectacular attacks by the Islamic State in Iraq and the Levant (Isis) and other al-Qaeda affiliates is accelerating.
In 2010, the low point for the al-Qaeda effort in Iraq, car bombings declined to an average of 10 a month and multiple-location attacks occurred only two or three times a year.
In 2013, so far there has been an average of 68 car bombings a month and a multiple-location strike every 10 days.
The UN says 5,740 civilians have been killed since January - almost double the figure it reported for the whole of 2010.Local groups
As bad as this seems, the more significant metrics to watch are those related to less spectacular attacks by nationalist or sectarian militants - mostly former soldiers or militia members who have been defending their streets from all-comers for a decade.
The foot-soldiers of the main insurgent groups - al-Qaeda affiliates, the Baathist die-hard Naqshabandi movement, plus the Iranian-backed Shia militants from Asaib Ahl al-Haqq or Kataib Hezbollah - are mostly "professional insurgents".
Membership of those groups is their insurgents' main source of income, and their activity levels are dictated by the prodding of the group's ideologues, funders and propagandists.
Sectarian tensions in the region, particularly those emanating from the crisis in Syria, and domestic Iraqi politics provide background drivers for the strengthening of local militant groups.
Attacks by these groups are increasing, but not as rapidly as the al-Qaeda stream.
At the low point of violence in Iraq in early 2011, the country suffered about 300 major security incidents a month. Throughout 2013, the monthly total of incidents has regularly topped 1,200.
But this is still well below the 6,000-plus incidents that were reported each month during the darkest days of the civil war-like conditions in late 2006 and early 2007.
What this tells us is that violence in Iraq remains largely limited to attacks undertaken by small militant cells, whilst the general population continues to stay uninvolved and civilian-on-civilian ethno-sectarian violence is still relatively rare.Revenge attacks
Will this continue to be the case? Nearly two years of intensified al-Qaeda mass-casualty attacks and sectarian massacres are beginning to severely test Shia patience, resulting in growing evidence of revenge attacks on Sunni mosques, preachers and civilians.
In Baghdad, the epicentre of sectarian tension, the Shia-dominated security forces collude with low-profile retaliatory actions by Asaib Ahl al-Haqq and the followers of the radical Shia cleric, Moqtada Sadr.
And to many Sunnis in Baghdad, the Iraqi security forces appear to be the ultimate Shia militia, corralling Sunnis into ghettoized neighbourhoods, where they are subject to repressive policing and economic isolation.
Sectarian attacks on the Sunni minority are even accelerating in Basra, the oil-rich province in the "deep south" of Iraq.
Nearly 20 Sunnis have been killed there in the last month, with some corpses dumped with notes explaining that they were killed in retaliation for the increasing number of al-Qaeda bombings in Basra.Stretched security forces
Civilians tend to kill other civilians when they feel the security forces cannot protect them, reflecting the reality that the Iraqi security forces have proven unable to reduce violence from either the al-Qaeda stream or neighbourhood-level militants.
Iraq's overworked counter-terrorism forces lack manpower, their funding and command relationships are snarled by bureaucracy and political infighting, and they cannot match the vast intelligence and aviation resources that the United States brought to the successful fight against al-Qaeda in Iraq from 2006 to 2010.
Baghdad and Washington have missed opportunities to co-operate on counter-terrorism since the US withdrawal in 2011.
Iraq's security forces have almost entirely abandoned the successful formula of population-focused counter-insurgency developed by the US-led coalition, instead falling back on counter-productive traditional tactics such as mass arrests and collective punishment.
Outside the cities, the Iraqi military cannot take the strain of continuous operations - its logistical capabilities collapsing and its aviation and intelligence capabilities proving insufficient to cover the country's vast rural expanses.
With much of the Saddam-era military expertise driven out by de-Baathification, the new million-man army built since 2003 did not have the institutional resilience needed to survive US withdrawal.Risk of lockdown
Most importantly the military campaign to defeat Iraq's insurgents is adrift from a concomitant political effort.
Though Iraqi politicians are adept at pulling the country back from sectarian meltdown at the last moment, there is no Iraqi equivalent to South Africa's Truth and Reconciliation Commission, nor are there currently Iraqi versions of Nelson Mandela and FW de Klerk - inspirational leaders capable of tackling the country's bitter history of dictatorship and inequality.
If Iraq continues down its current path a meltdown will probably occur, not on the scale of 2006-2007 but nonetheless plunging the country into full military lockdown.
It would be easy to imagine Iraq's Sunnis living under a semi-permanent state of military occupation by the Iraqi security forces, an outcome that could see Iraq's security crisis stretch out beyond the current decade and become a part of the regional landscape.