Iraq’s top Shiite cleric on Monday gave his support to the new government battling the Islamic State group as militants unleashed a wave of deadly attacks on the country’s majority Shiite community, killing at least 43 people.

The blitz by the militants this summer plunged Iraq into its worst crisis since U.S. troops left at the end of 2011. While there was no claim of responsibility for Tuesday’s attacks, they seemed likely calculated by the group to sow fear among Iraqis and keep pressure on the new Shiite-led government in Baghdad.

Prime Minister Haider al-Abadi, who took office last month, met Monday with top Shiite cleric Grand Ayatollah Ali al-Sistani in the southern city of Najaf. He said after their talks that al-Sistani welcomed the recent formation of the government that Al-Abadi now leads. […]