This will confirm for the first time that Ibrahim al-Asiri, a senior al-Qa’ida bomb maker and terrorist coordinator, was killed two years ago in a United States counterterrorism operation in Yemen. Al-Asiri built explosive devices that were used in the failed Christmas Day 2009 underwear bomb attack and the disrupted printer cartridge bomb plot in 2010. He also built an explosive device intended to be used against a passenger aircraft in 2012, and the device used in the attempted assassination of the former Crown Prince of Saudi Arabia. Al-Asiri’s death significantly handicapped al-Qa’ida in the Arabian Peninsula. The United States...