In March and April 2018, the US President Donald Trump repeatedly declared the intention to withdraw the American troops from Syria. "Our primary mission was getting rid of ISIS (Islamic State, an international terrorist group prohibited in Russia). We’ll be making a decision very quickly, in coordination with others (participants of the Western coalition headed by the US) in the area, as to what we will do." – said Trump to the leaders of the Baltic states in Washington.
The President of the USA directly stressed mismatch of the costs and achievements when answering persuasions of the Saudi officials, who was asking to maintain American military presence in Syria and Iraq. "We spent over USD 7 trillion in the Middle East and did not gain anything. Or less than nothing", – summarized the American leader.
At the same time, Pentagon believes that there is a long way to a victory over ISIS. Influential officials of the State Department have roughly same opinion. The difference in the opinions on this issue is explicable: the American president in his statements focuses on the internal audience in the country in order to comfort public opinion and keep up his level of support. As for the military officials and politics, they, first of all, defend a position of reinforcing influence of the military and industrial establishment of the USA.
There actually are solid reasons for the US leadership to maintain military presence in Syria. Keep in mind that Washington, in violation of all international laws and without an invitation from the Syrian government, placed the troops on the Syrian territory. According to estimates, there are 1 to 3 thousand American soldiers on nine military assets, Pentagon uses in its interests several airfields.
However, a main reason is consolidation of the Russian military forces in Syria, which use airport of Hemeimeem and sea port of Tartus in order to provide aid to Damascus in destruction of the terrorist international on the country territory. They clearly understand, over the ocean, which role, for three years of its military presence, Russia played not only with its participation in war, but also in reconstruction of the Syrian army combat effectiveness. Restraining Russia in Syria is one of the main Pentagon objectives.
Second and very painful reason for maintaining American presence in the country is an increasing influence of Iran in Iraq, Syria and Lebanon. Washington unilaterally pulled out from the agreement on Iran nuclear program, flagrantly violating international obligations by that. Donald Trump intends to renew political and economic sanctions against Iran and requests that the European allies unconditionally join to phasing out the relations with this country.
Washington policy towards Tehran is zealously supported by Tel Aviv, which sees development of Iran's co-operation with Iraq, Syria and Lebanon as a threat to its own national security. The USA, being a staunch ally of Israel, simply obliged to maintain American military presence in Syria in order to tightly control individual sections of the Syria-Iraq border, which may be used as transit points for military cargoes from Iran to Lebanon.
And more. Pentagon formed and provided with weapons and equipment Kurdish forces of Syrian Democratic Forces (SDF) in the north of Syria, which possess high combat potential. In the future, i.e. after defeat of the terrorist international, SDF can and will defend their own specific national interests, dictate to the Syrian government the conditions that do not support national and territorial unity of the state.
In its turn, the Turkish leadership considers Kurdish forces as terroristic and does not intend to accept such a powerful military force, deployed in the frontier zone. Turkey initiated military operation against Kurds in Afrin enclave, and claims to conduct a large-scale "mop-up" operation of the areas along the banks of Euphrates river and in the north-west of Syria, where most of the US Armed Forces pivot points are deployed. In such conditions, Washington is forced to restrain Turkish appetite "on the spot", keeping a balance between Kurds included into so-called "Western coalition" and Ankara, which is one of most combat effective NATO members. Pentagon decided to demonstrate SDF combat capability in order to "pacificate" the Turks, when initiated an operation of suppressing the ISIS squadrons in the north-west of Syria in April. Operation is characterized as a low-grade offensive with extensive application of American combat aviation and artillery against the enemy.
In turn, the Turkish leadership intensified the efforts of pulling over on its side the Syrian opposition combatants basing on the agreements, which forced them out of the military activities in the central south regions to "de-escalation zones" in order to use them against Kurdish SDF forces. That is one more "headache" for the Americans. Donald Trump may be considering a possibility to reduce load on the American troops in Syria at the expense of creating and directing to this country an international contingent of forces. For example, Arabian or multinational. However, time for their deployment is hopelessly lost. The countries guaranteeing settlement of the situation in Syria (Russia, Iran and Turkey) will block such proposal in the UN. The world is not ready to send its soldiers to perform a military adventure just as well.
Obviously, that in the nearest future, Washington does not intend to phase down the military presence in Syria. Moreover, all the efforts of the Syrian leadership to use the UN as a platform to oppose this are doomed to failure: the USA openly ignore international law in an effort to achieve its objectives. From the other hand, Pentagon remembers an explosion of the American military barrack in West Beirut in October 1983 and 263 dead American soldiers and officers. Repeating of such scenario is hardly included to the plans of the American strategists, this will make Washington position even more complex: The USA are very much tangled in their Middle East intrigues and cannot propose to the region a comprehensive solution of the accumulated contradictions.