The Syrian 'Civil War' and the Rise of ISIS / ISIL / Daesch

Main articles: Syrian Civil War and Timber Sycamore

The United States has provided extensive lethal and non-lethal aid to many Syrian militant groups fighting against the Syrian government, an ally of Russia, during the Syrian Civil War. The Syrian government has directly accused the United States of sponsoring terrorism in Syria. The United States government was also criticized by Iran for its silence following the beheading of a child by the Islamist group Nour al-Din al-Zenki, a group that is a recipient of US military aid and is accused of many war crimes by Amnesty International.

Turkish President Recep Tayyip Erdogan has also accused the United States of supporting ISIS in Syria, claiming Turkey has evidence of U.S. support for ISIS through pictures, photos, and videos, without further elaborating on said evidence or providing any. 

An investigation by journalists Phil Sands and Suha Maayeh revealed that rebels supplied with weapons from the Military Operations Command in Amman sold a portion of them to local arms dealers, often to raise cash to pay additional fighters. Some MOC-supplied weapons were sold to Bedouin traders referred to locally as "The Birds" in Lajat, a volcanic plateau northeast of Daraa, Syria. According to rebel forces, the Bedouins would then trade the weapons to ISIL, who would place orders using the encrypted WhatsApp messaging service. Two rebel commanders and a United Kingdom weapons monitoring organization maintain that MOC–supplied weapons have made their way to ISIL forces.

Another study conducted by private company Conflict Armament Research at the behest of the European Union and Deutsche Gesellschaft für Internationale Zusammenarbeit found that external support for anti-Assad Syrian rebels "significantly augmented the quantity and quality of weapons available to [ISIL] forces," including, in the most rapid case diversion they documented, "anti-tank weapons purchased by the United States that ended up in possession of the Islamic State within two months of leaving the factory."

1956–1957: Syria

See also: CIA activities in Syria

As a result of the 1954 Syrian coup d'état, the Second Syrian Republic was ruled by Nasserist civilian politician Sabri al-Asali, in close collaboration with the army, challenged by the US-backed far right Syrian Social Nationalist Party. In 1956 Operation Straggle was a failed coup plot against al-Asali. The CIA made plans for a coup for late October 1956 to topple the Syrian government. The plan entailed takeover by the Syrian military of key cities and border crossings. The plan was postponed when Israel invaded Egypt in October 1956 and US planners thought their operation would be unsuccessful at a time when the Arab world is fighting "Israeli aggression." The operation was uncovered and American plotters had to flee the country.

In 1957 Operation Wappen was a second coup plan against Syria, orchestrated by the CIA's Kermit Roosevelt. It called for assassination of key senior Syrian officials, staged military incidents on the Syrian border to be blamed on Syria and then to be used as pretext for invasion by Iraqi and Jordanian troops, an intense US propaganda campaign targeting the Syrian population, and "sabotage, national conspiracies and various strong-arm activities" to be blamed on Damascus. This operation failed when Syrian military officers paid off with millions of dollars in bribes to carry out the coup revealed the plot to Syrian intelligence. The U.S. Department of State denied accusation of a coup attempt and along with US media accused Syria of being a "satellite" of the USSR.

There was also a third plan in 1957, called "The Preferred Plan". Alongside Britain's MI6, the CIA planned to support and arm several uprisings. However, this plan was never carried out and the Syrian Republic survived until its 1958 union with Egypt in the United Arab Republic, ruled from Cairo by Gamal Abdel Nasser.

2005–2017: Syria

Main articles: Timber Sycamore, CIA activities in Syria, and American-led intervention in the Syrian Civil War

In 2005, after a period of co-operation in the “War on Terror”, the Bush administration froze relations with Syria, a dictatorship. According to US cables released by WikiLeaks, the State Department then began to funnel money to opposition groups, including at least $6 million to the anti-government satellite channel Barada TV and the exile group Movement for Justice and Development in Syria, although this was denied by the channel. This secret backing continued under the Obama administration until at least April 2009 when US diplomats expressed concern the funding would undermine US attempts to rebuild relations with Syrian President Bashar Al-Assad.

In April 2011, after the outbreak of the Syrian civil war in early 2011, three "key U.S. Senators", Republicans John McCain and Lindsay Graham, and Independent Joe Lieberman, said in a joint statement, urged Obama to "state unequivocally" that "it is time to go". In August, 2011, the U.S. government called on Syrian President Assad to "step aside" and imposed an oil embargo against the Syrian government to bring it to its knees. Starting in 2013, the U.S. also provided training, weapons and cash to Syrian vetted "moderate" rebels, and in 2014, the Supreme Military Council. In 2015, Obama reaffirmed that "Assad must go".

In March 2017 Ambassador Nikki Haley told a group of reporters that the US's priority in Syria was no longer on "getting Assad out." Earlier that day at a news conference in Ankara, Secretary of State Rex Tillerson also said that the "longer term status of President Assad will be decided by the Syrian people." While the US Defense Department's program to aid predominantly Kurdish rebels fighting the Islamic State of Iraq and the Levant (ISIL) continued, it was revealed in July 2017 that US President Trump had ordered a "phasing out" of the CIA's support for anti-Assad rebels.

In October 2017, Rex Tillerson declared that "the reign of the Assad family is coming to an end" despite recent battlefield gains by Assad's forces. In April 2018, Army General James Votel told lawmakers he did not know whether 'Assad must go' remained a U.S. policy objective; Lindsay Graham responded "If you don't know I doubt if anybody knows, …"; and it was reported that the Trump administration has indicated that ousting Assad is no longer a specific policy goal but it cannot envision political stability if he remains.