FALLUJAH, Iraq — Hundreds of Iraqis set alight U.S. and Israeli flags on Wednesday as they celebrated the impending pullout of American forces from the country in the former insurgent bastion of Fallujah. Shouting slogans in support of the “resistance,” the demonstrators held up banners and placards inscribed with phrases like, “Now we are free” and “Fallujah is the flame of the resistance.” Surrounded by the Iraqi army, demonstrators carried posters bearing photos of apparent insurgents, faces covered and carrying weapons. They also held up pictures of U.S. soldiers killed and military vehicles destroyed in the two major offensives against...