January 23, 2019
Syria Conflict Overview: 2011-2018
2011: Protests Emerge
In March 2011, the arrest of a group of school children
triggered protests in the southern Syrian province of Dar’a.
Mostly peaceful demonstrations called for political and
economic reform, although violence was reported at times.
As security forces responded with mass arrests and at times
opened fire, protests spread to other provinces. The
opposition movement eventually coalesced into two
umbrella groups—one political, one armed—with the
leadership of both based primarily in exile. Political groups
established the Syrian National Council (SNC), which
remained fractured in the absence of a shared vision for
Syria’s future. Military defectors formed the Free Syrian
Army (FSA), which claimed leadership over the armed
opposition but whose authority was generally unrecognized
by local armed groups, including armed Islamists. Ongoing
violence, primarily but not exclusively on the part of the
Syrian government, prompted President Obama in August
2011 to call for Syrian President Asad to step aside.
Meanwhile, the Al Qaeda (AQ) affiliate in neighboring Iraq
(the Islamic State of Iraq, ISI) sent members to Syria under
the banner of a new group known as the Nusra Front. In
December 2011, the first Nusra Front suicide attacks hit
government buildings in Damascus.
The conflict became increasingly violent, as the
government began to use artillery and fixed wing aircraft
against opposition targets. Extremist attacks became more
frequent—between November 2011 and December 2012,
the Nusra Front claimed responsibility for nearly 600
attacks in Syria. In February 2012, the United States closed
its embassy in Damascus, citing security concerns. Local
armed groups began to seize pockets of territory around the
country, primarily in rural areas. A July bombing in central
Damascus killed several senior regime officials, including
the Minister of Defense. Concerns about potential
government use of chemical weapons (CW) led President
Obama in August to declare the use of chemical weapons to
be a “red line” for the United States.
The international community increased efforts to reach a
negotiated solution to the conflict. In June, the United
States and Russia signed the Geneva Communiqué, which
called for the establishment of a transitional governing body
in Syria with full executive powers. The document, which
became the basis of future negotiations between the
government and the opposition, did not clarify the role of
Asad in any future government. Meanwhile, Syria’s
political opposition settled into its present form, known as
the National Coalition of Syrian Revolutionary and
Opposition Forces—generally shortened to the Syrian
Opposition Coalition (SOC), or Etilaf in Arabic.
Figure 1. Syria
Source: CRS, using ESRI, and U.S. State Department data.
2013: Proxy War, ISIS, Chemical Attacks
In March 2013, rebels seized the city of Raqqah, which
became the first provincial capital to fall out of government
control. A series of other opposition victories in the area led
the government effectively to concede control of Syria’s
rural northeast. These rebel victories prompted increased
involvement by external allies of the Syrian government—
including Lebanese Hezbollah, Iran, and Russia—to bolster
the Asad regime. Meanwhile, the United States, Turkey,
and some European and Arab Gulf states increased their
support to the Syrian opposition. While nominally united
under the Friends of Syria framework, regional and
Western states differed in their goals and strategies, and
thus in their support for various factions. Separately, ISI
leader Abu Bakr al Baghdadi announced the merger of his
group and the Nusra Front into the Islamic State of Iraq and
Al Sham (ISIS/ISIL), a move opposed by Al Qaeda’s
central leadership in Afghanistan. The merger triggered
extensive infighting among Syrian jihadist groups.
Concerns about Syrian government use of CW grew in
2013. In April, the United Kingdom and France claimed
that the Syrian government had used chemical weapons on
multiple occasions since December 2012. In August, a sarin
gas attack attributed to the Syrian government killed an
estimated 1400 people in the Damascus suburb of Ghouta.
President Obama requested congressional approval of a
limited authorization for the use of military force to
respond. Congress debated, but did not authorize the
request. Russia subsequently negotiated an agreement for
the Syrian government to become a party to the Chemical
Weapons Convention, dispose of its declared chemical
weapons stockpiles (completed in 2016) and destroy
production facilities (completed in 2018).
Syria Conflict Overview: 2011-2018
2014: Operation Inherent Resolve Begins
2017: Counter-IS Operations Advance
In February, Al Qaeda severed ties with ISIS, which went
on to seize vast stretches of territory in central and northeast
Syria and northern Iraq. In June, ISIS declared a caliphate
with its capital at Raqqah. The group changed its name to
the Islamic State (IS), and thousands of additional foreign
fighters traveled to Syria and Iraq to join its ranks. In
August, the United States began air strikes in Iraq to stop
the IS territorial advance there, and to reduce the threat to
U.S. personnel in Iraq. In September, the United States
expanded air strikes to Syria at Iraq’s request, to prevent the
Islamic State from using Syria as a base for operations in
Iraq. A subsequent air campaign to lift the IS siege on the
Syrian Kurdish town of Kobane brought the United States
into partnership with the Kurdish People’s Protection Units
(YPG). In September, Congress authorized a train and
equip program for select Syrian forces. The program was
designed to build new local force units capable of fighting
the Islamic State, protecting opposition-held areas, and
“promoting the conditions for a negotiated settlement to end
the conflict in Syria.” In October, the Defense Department
established Combined Joint Task Force-Operation Inherent
Resolve (CJTF-OIR) to formalize military operations
against IS forces in Iraq and Syria.
In January 2017, Russia—backed by Turkey and Iran—
initiated a series of peace talks in the Kazakh capital of
Astana between Syrian government and opposition forces.
The talks became known as the Astana process, and were
seen by some as an effort to circumvent the U.S.-backed
Geneva process. The Astana process established three
opposition-held areas as “de-escalation” zones in an effort
to reduce violence. Separately, the United States, Russia,
and Jordan established a southwest ceasefire area in Dar’a.
In April, a suspected nerve agent attack by government
forces on the rebel-held town of Khan Sheikhoun in Idlib
province killed an estimated 80-100 people. The United
States struck Al Shayrat airfield in Homs province, from
which U.S. intelligence sources had concluded the attack
was launched. In a series of incidents in May and June, U.S.
forces also carried out defensive strikes against Syrian
government and allied forces deemed to be threatening U.S.
forces and local partners in Syria. In June, SDF forces
began operations to retake the IS capital at Raqqah, and
SDF forces recaptured the city in October. In December,
U.S. military officials announced that roughly 2,000 U.S.
personnel were operating in Syria, and that 98 percent of
territory formerly held by IS forces had been liberated.
2015: Syria Train & Equip Begins
2018: Syrian Government Recovers
In 2015, the Syrian government faced additional territorial
losses. Opposition forces captured the provincial capital of
Idlib in northwestern Syria and surrounding areas with the
support of Al Qaeda-linked fighters. IS fighters seized
territory in Homs province, and Kurdish fighters expanded
their control along the Turkish border. In May, the United
States began training recruits for the Syria Train and Equip
Program. In mid-2015, Russia began a military buildup in
Syria, and started air strikes in September—targeting
opposition groups in addition to IS fighters. In October, the
first U.S. Special Operations Forces deployed to Syria to
support local partner forces. Challenges in implementation
led the Obama Administration to modify the Syria Train
and Equip program to focus on equipping existing units
commanded by vetted leaders. Kurdish YPG forces aligned
with a small number of non-Kurdish groups to form an
umbrella group known as the Syrian Democratic Forces
(SDF), which began to receive U.S. support.
2016: Ceasefires Fail; Battle for Aleppo
The United States attempted to work with Russia to reduce
the violence in Syria, which both the Syrian government
and opposition described as a prerequisite to their continued
participation in U.N.-led peace talks. The two countries
twice attempted to use their leverage with the Syrian
opposition and government, respectively, to implement a
cessation of hostilities. Both initiatives were unsuccessful.
In contrast, the counter-IS campaign successfully severed
much of the group’s access to the Turkish border—a key
supply and foreign fighter transit route. However, Turkey
strongly opposed the participation of YPG fighters in the
campaign, and launched an operation inside Syria aimed at
neutralizing IS forces and preventing Kurdish YPG forces
from consolidating control along the Syria-Turkey border.
Meanwhile, regime and opposition forces battled for control
of Aleppo—Syria’s largest city. In December, regimebacked forces took full control of Aleppo, in a battle the
U.N. described as involving war crimes on all sides.
External actors escalated military operations in Syria.
Tensions flared between Iran and Israel, as the latter
increasingly targeted Iranian facilities and personnel inside
Syria. Turkey launched a military operation inside Syria
targeting Kurdish forces and causing a manpower drain
from counter-IS operations in eastern Syria. The United
States struggled to reduce tensions in the city of Manbij, as
Turkey threatened to expand its military campaign unless
Kurdish forces withdrew east of the Euphrates River.
By early 2018, the U.S. intelligence community assessed
that the Syria conflict had “decisively shifted in the Syrian
regime’s favor.” By mid-2018, the Syrian government had
recaptured most areas designated as de-escalation zones in
2017 through a combination of military force and coercive
surrender agreements. By late 2018, only parts of the Idlib
de-escalation area remained outside government control,
held by a constellation of opposition and AQ-linked groups.
In 2018, State Department officials described U.S. Syria
policy as seeking (1) the enduring defeat of the Islamic
State; (2) a political settlement to the Syrian civil war per
U.N. Security Council Resolution 2254; and (3) the
withdrawal of Iranian-commanded forces from Syria.
Officials stated that the United States planned to remain in
Syria to stabilize areas liberated from IS control, and to
train local partners to hold these areas so that IS forces
could not re-emerge. In December, President Trump stated
that the Islamic State had been defeated in Syria, and that
U.S. troops would be withdrawing “now.” Subsequent
statements by senior Administration officials suggested that
the withdrawal could take several months, and was
conditional on reaching an agreement with Turkey that
guaranteed the protection of U.S.-backed Kurdish forces in
Syria. The year ended amid uncertainty regarding the
withdrawal and its impact on U.S. programs in Syria.
Carla E. Humud, Analyst in Middle Eastern Affairs
Syria Conflict Overview: 2011-2018
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