But the president's aspirations have long run into resistance, as his own national security officials argued that abandonment of such troubled countries could have catastrophic consequences -- such as when the United States pulled out of Iraq at the end of 2011, leaving a vacuum that fostered the rise of the Islamic State in Iraq and Syria. Mr. Trump has also repeatedly pushed to withdraw from Syria, but several hundred U.S. troops remain stationed there, partly to protect coveted oil fields held by American-backed Syrian Kurdish allies from being seized by the government of President Bashar al-Assad of Syria. The current deliberations over withdrawals would not affect those in Syria, officials said. The plan under discussion to pull out of Somalia is said to not apply to U.S. forces stationed in nearby Kenya and Djibouti, where American drones that carry out airstrikes in Somalia are based, according to officials familiar with the internal deliberations who spoke on the condition of anonymity. Keeping those air bases would mean retaining the military's ability to use drones to attack militants with the Shabab, the Qaeda-linked terrorist group -- at least those deemed to pose a threat to American interests.