Following a swift offensive by Syrian opposition forces that captured major cities and ultimately resulted in the collapse of Bashar al-Assad’s regime, US President Joe Biden publicly acknowledged the role of the United States in the rebel success.

“Our strategy has altered the power dynamics in the Middle East,” Biden stated earlier this week.

“By combining support for our allies, implementing sanctions, engaging in diplomacy, and utilizing targeted military action when necessary, we are witnessing new possibilities emerging for the people of Syria and the broader region.”

Biden’s remarks, along with a surge of speculation suggesting that Washington and Israel were covertly supporting the offensive, have reignited discussions regarding the US’s involvement in Syria over the last fifteen years.

The United States initially entered the Syrian civil war in 2013 under the Barack Obama administration through CIA operations, followed by the deployment of US troops in 2014 to combat the Islamic State (IS) group, which had seized significant territories in both Iraq and Syria.

However, by the time President Donald Trump assumed office, the US presence in Syria had diminished to 900 troops stationed in the northeast, where Kurdish-led forces held sway.

Just prior to the rebel takeover over the weekend, reports indicated that the United Arab Emirates was facilitating discussions between the Assad government and the US.

This analysis focuses on the United States’ involvement in the Syrian conflict, particularly regarding the various groups it has supported or refrained from supporting over the last ten years.

Syrian Democratic Forces

To begin, it is essential to examine the Syrian Democratic Forces (SDF), which primarily consists of fighters from the People’s Protection Units (YPG), a faction linked to the Kurdistan Workers’ Party (PKK). The US designates the PKK as a terrorist organization.

The US aimed to assist the SDF in its efforts to defeat and prevent the resurgence of ISIS in Syria.

By 2012, Kurdish forces had successfully compelled the Syrian army to withdraw from northeastern Syria. The SDF was formed in 2015 as a coalition of mainly Kurdish groups, with some representation from Arab and other ethnic factions.

Over the next decade, the SDF managed to control approximately 25% of Syrian territory, establishing an administration that operated independently from the central government in Damascus.

In 2019, following President Trump’s announcement of a troop withdrawal, the SDF reached an agreement with the Assad regime. Currently, around 900 of the approximately 2,000 US troops remain stationed in Syria. This agreement permitted Syrian army forces to re-enter certain areas under SDF control to assist in defending against Turkish military actions.

Since the fall of the Assad regime, the Syrian Democratic Forces (SDF) have experienced territorial losses to Turkish-backed factions, prompting the United States to take measures to mitigate the offensives against the SDF.

In the Pentagon’s budget proposal for 2024 under the Biden administration, $156 million has been earmarked for the Counter-Terrorism Equipment Fund (CTEF) aimed at combating ISIS in Syria. This funding is designated for various purposes, including training, equipment, logistics, and infrastructure. For the 2025 budget, the Pentagon has requested $148 million for the same fund, following a $160 million allocation in 2023.

The budget outlines that a significant portion of this funding will be directed towards the SDF and, by extension, the People’s Protection Units (YPG).

According to a Pentagon budget document, “CTEF will continue providing small arms and light weapons to support the SDF.”

While the SDF did not participate in the 2024 rebel offensive that led to the ousting of the Assad government, they expressed their support and welcomed his departure.

Syrian Free Army

Another beneficiary of CTEF funding is the Syrian Free Army (SFA), which should not be confused with the Free Syrian Army (FSA), a coalition of various factions within the Syrian opposition that is now referred to as the Syrian National Army (SNA).

The Syrian Free Army (SFA) operates in the southeastern region of Syria, close to the borders with Iraq and Jordan. It has received support from the United States at the al-Tanf military base, a strategic location in the Syrian desert along the route connecting Damascus and Baghdad.

According to a Pentagon budget document, the SFA is described as an essential ally for coalition forces stationed near the At Tanf Garrison (ATG) in southeastern Syria.

Previously known as Maghawir al-Thawra, the SFA has been trained and supported by the US for several years.

The US government asserts that its assistance to the group has been aimed at combating the Islamic State (IS). Additionally, the SFA has been utilized to help ensure security around the al-Tanf Garrison, which US Air Force Colonel Daniel Magruder has suggested could serve as a strategic leverage point for the US in determining a favorable resolution in Syria.

During the rebel offensive in 2024, the Syrian Free Army had a limited role, particularly in Homs province, where they managed to repel Syrian government forces.

Operation Timber Sycamore

Recently, a leaked email from 2012 has gained attention, in which Jake Sullivan, then assistant national security advisor under President Obama, informs former Secretary of State Hillary Clinton that “AQ is on our side in Syria,” referring to al-Qaeda.

This email excerpt has been referenced as evidence of US support for both al-Qaeda and IS in Syria.

Sullivan notes in the same email that Al-Qaida leader al-Zawahiri urged Muslims in Turkey and the Middle East to support rebel forces in their struggle against the backers of Syrian President Assad through an internet video. He also advised the Syrian populace to avoid depending on the Arab League, Turkey, or the United States for help.

There are no documented instances indicating that the US directly financed the operations of IS or al-Qaeda within Syria.

However, a year later, the Obama administration sanctioned a CIA initiative known as Timber Sycamore, which involved training and arming select Syrian rebels to oppose the Assad regime.

The CIA allocated a total of $1 billion to this program. Nevertheless, the US struggled to maintain oversight of the rebels they supported, facing challenges as the al-Nusra Front, a former al-Qaeda affiliate and precursor to Hay’at Tahrir al-Sham (HTS), made considerable progress against both al-Qaeda and the Assad government.

The Trump administration ultimately terminated Timber Sycamore, and Trump attempted to withdraw US troops from Syria completely, but this effort was unsuccessful.

Hay’at Tahrir al-Sham

HTS, referred to in English as the Committee for the Liberation of the Levant, is the primary Syrian opposition group responsible for the swift dismantling of the Assad regime.

It was established in January 2017 as the most recent rebranding of Jabhat al-Nusra, also referred to as the Nusra Front, a radical rebel faction initiated by Ahmed al-Sharaa in 2012 to challenge Assad’s regime and establish a Sunni Islamic state in Syria.

In its initial months, Nusra collaborated with the Iraqi group that would eventually evolve into ISIS. However, in 2013, it declared its loyalty to al-Qaeda, leading to a rivalry between Nusra and ISIS.

As time progressed, the association with al-Qaeda became burdensome for Nusra, prompting its leader, Abu Mohammad al-Jolani, to seek distance from al-Qaeda’s global jihadist agenda and to pursue international recognition.

In 2016, Nusra officially severed ties with al-Qaeda, rebranding itself as Jabhat Fatah al-Sham, and systematically eliminated factions intent on conducting attacks beyond Syria. Subsequently, in 2017, it merged with several smaller groups and adopted the name HTS.

The organization is designated as a terrorist group by the United States, which has never provided direct support to HTS.

In 2021, former US ambassador James Jeffrey informed PBS News that HTS had reached out to Washington seeking support, a request he chose to disregard.

“Why should I… take the high-risk position of urging somebody get dropped from the terrorist list?” Jeffrey remarked to PBS.