(CNN) -- Fallujah and Ramadi may have been sites of heavy bloodshed in recent days, but the Sunni Muslims of Iraq's Anbar Province, where the two cities are located, have long held a contemptuous attitude towards the embattled government of Prime Minister (and Shia Muslim) Nuri al-Maliki. Iraqi politics and many aspects of economic and social affairs have come to be dominated by antagonistic relationships between the country's Sunni and Shia populations. Nowhere is that more evident than in Anbar. For all intents and purposes, Fallujah and Ramadi are now out of the control of the central government and are now ruled under the authority, to differing degrees, of Sunni militiamen, local (tribally influenced) police, and extremist militants from the Islamic State in Iraq and Syria, or ISIS.
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Recent fighting in Anbar province poses serious challenge to Iraqi government
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Al Qaeda-linked militants reportedly fighting alongside tribal leaders in Fallujah
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2013 was deadliest year in Iraq since 2008
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U.S. and coalition forces suffered some of worst losses during Iraq War in Anbar province
For Maliki and @placeholder, ISIS remains an extremely concerning problem.