A leading Iraqi doctor who co-authored a study on Iraq’s death toll since the U.S. invasion has been barred from entering the United States. Riyadh Lafta was set to give a talk at the University of Washington on the growing rise in cancer rates among Iraqi children. U.S. immigration officials ignored Lafta’s visa request a half-dozen times before finally turning him down. Lafta will still make the speech — he’s been invited to speak at Simon Fraser University in Canada.