Nearly 2,000 people have been killed in the last two months as al Qaeda and Sunni Islamist insurgents, invigorated by the Sunni-led revolt in neighboring Syria and by Iraqi Sunni discontent at home, seek to revive the kind of all-out inter-communal conflict that killed tens of thousands in 2006-2007.

Just this week, multiple bombings battered Shiite and Sunni neighborhoods in the Iraqi capital Baghdad, where at least 70 people were killed on Monday and 25 on Thursday.

The renewed bloodletting reflects worsening tensions between Iraq’s Shiite-led government and its Sunni minority, seething with resentment at their treatment since Saddam Hussein was overthrown by the U.S.-led invasion of 2003 and later hanged.