WASHINGTON – An al-Qaida leader believed to have played a key role in the bombing of a CIA post in Afghanistan last December was apparently killed by an American missile strike last week, a senior U.S. official said Wednesday. The counterterrorism official said Hussein al-Yemeni was believed killed in a strike in Miram Shah, the main town in North Waziristan. The official spoke on condition of anonymity to discuss sensitive information. Drone strikes in Pakistan's border region, largely conducted by the CIA, have escalated in recent months, proving an effective way to target al-Qaida and Taliban leaders hiding in the...