Sowing death

In January 2004, Abu Musab al-Zarqawi, the Jordanian-born leader of jihadist insurgents in Iraq, wrote a letter to Osama bin Laden. Dismissing Americans as “the most cowardly of creatures,” who would leave the country soon enough, Zarqawi turned to the apparently “insurmountable obstacle,” the Shiite majority in Iraq, “the lurking snake, the crafty and malicious scorpion, the spying enemy, and the penetrating venom.” With al Qaeda’s official endorsement and financial support, Zarqawi promised a campaign that would destabilize Iraq, awaken Sunnis and annihilate Shiite apostates. To those who claimed that the Islamic nation was not ready for a bloody battle, Zarqawi had a ready reply: “This is exactly what we want.”

Two years later, a 500-pound guided bomb, dropped by an American F-16 air-

Lefteris Pitarakis / Associated Press 2014 Militants with the Islamic State place their flag on a hilltop in Kobani, Syria, where fighting had intensified between Syrian Kurds and Islamic State militants.

Tauseef Mustafa / AFP / Getty Images 2014 Demonstrators hold up the Islamic State flag in Gaza.

Black Flags The Rise of ISIS By Joby Warrick (Doubleday; 344 pages; $28.95)