The collective group of misfits comprised of Islamic extremists and paid mercenaries from as far away as Africa and China most often referred to under the collective banner, ISIS, first invaded the country of Syria around 2012. For the next three years, they, and insurgents fighting under a variety of names and flags wreaked havoc on Syria and Iraq gaining control of 41,000 square miles in the two countries when the US armed forces got involved in 2014.
By late September of 2015 the Syrian government officially invited Russian armed forces into the country to help their army confront the foreign invaders. At the time, ISIS was operating openly in large parts of the country bordering Turkey. While it’s historically said that an army marches on its stomach; in the case of the foreign terrorist operatives in Syria, it could be argued they marched on oil instead.
In fact, they not only ran on oil, they were thriving on it as late as mid November of that year. At the time, there were strict sanctions in place barring the sale of Syrian oil from ISIS-controlled caliphates. Those were, however, not a deterrence as they had created a pipeline on wheels. A convoy of oil tankers ran down the highway so large that it could literally be seen from space. It ran a 2-way corridor across the Turkish border where the Turkish government under Erdogen at a minimum turned a blind eye to an operation that swapped oil for supplies — military and other.
This free-for-all came to a close just 6 short weeks after Russia first started setting up camp in the country. On November 18, 2015 a team of long-range bombers joined Su-34, Su-25, and Su-24M jets in the destruction of around 500 ISIS-run oil and gas trucks. This marked the day that the main supply artery was permanently shut down and really amounted to the beginning of the end of a clan of ruffians that had caused so much pain and suffering in that part of the world.