Mikhail Klimentyev / Sputnik / Reuters

As the United States seemed moving closer to striking government targets in Syria Wednesday morning, Donald Trump opened the day with a series of harsh tweets. But rather than threatening the Syrian regime directly, he opened up by threatening Russia.

Moments later, a Russian Foreign Ministry spokeswoman said “smart missiles should fly towards terrorists not the legitimate government that has been fighting international terrorism on its territory for several years.”

Trump’s choice of Twitter target was unusual, given that he has typically avoided criticizing the Russian government in public. But since an alleged chemical-weapons attack in the Syrian city of Douma over the weekend, which Western governments are attributing to the Assad regime, Trump like others in his administration has focused criticism on Assad’s enablers in Russia. Russia claims it is fighting terrorists opposed to the legal government in Syria—some of whom the U.S. sees as legitimate opposition and has supported. In 2012, U.S. officials believed Assad’s days were numbered; Russia’s 2015 military intervention in Syria changed the course of the civil war in Assad’s favor.

Russia continues to be Assad’s greatest supporter even as the Syrian conflict has killed more than 500,000 people, created more than 5 million refugees, and flattened entire cities. Here are the ways Russia enables the regime:

On the ground: Russian intervention in the Syrian civil war began on September 30, 2015, three-and-a-half years after the conflict erupted. Since that time, Russia has carried out airstrikes on targets inside Syria that it says are controlled by terrorists. It also has military advisers and special forces operating inside the country. In a puzzling statement last December, Defense Minister Sergei Shoigu said that 48,000 Russian military men had gained experience in Syria, without elaborating on what kind of experience. Russian mercenaries are also active in the country—as evidenced by the dozens who were killed in February by the U.S. military. The Kremlin denies any direct connections to the mercenaries.

Although Russian airstrikes targeted groups including ISIS and organizations that have connections to al-Qaeda, Russia also helped Assad against other, more moderate rebel groups that have fought against the regime. Prior to Russia’s intervention, a coalition of rebel groups had pushed Assad into a corner, seizing large parts of the country from the government, including Aleppo, the largest city. But with Russian help, as well as military support from Iran and Hezbollah, the Shia militia group, Assad has recaptured much of the country—and nearly all of its population centers.

Through diplomacy: If Russian military intervention assured Assad’s survival, its diplomatic support has saved him from international sanctions—if not from condemnation. Russia is a veto-wielding member of the United Nations Security Council, which means it has effectively used its veto power to suppress international action against the Syrian government. This was evident most recently on Tuesday, when Moscow stopped a U.S.-sponsored resolution to investigate the attack in Douma and determine who was responsible for the suspected use of chemical weapons there.

Russia has used its veto power concerning Syria 12 times at the UN, according to a list compiled by RTE, the Irish broadcaster. Four of those vetoes blocked resolutions that would have investigated chemical-weapons use in the country; a fifth stopped sanctions over the use of such weapons. Russia has previously also vetoed resolutions to stop the fighting in Aleppo, since violently retaken by the Syrian government; to refer Syria to the International Criminal Court for war crimes; to condemn the regime’s actions; and to sanction it for using heavy weapons in the conflict.

When the Syrian government was accused of a massive sarin gas attack that killed thousands in 2013, Russia was critical in helping save the regime from the military consequences the United States had threatened. Instead, it helped broker a deal to get Syria to declare its chemical weapons and move them out of the country. The deal did remove many tons of those substances, but Assad kept undeclared stockpiles that have been used in other attacks since.

Separately, Russia has led its own initiatives for  peace in Syria—with varying success. Some rebel groups have talked to the regime as part of those efforts, but with Assad’s military gains it is unclear if the Syrian government now has any incentive to talk to those it regards as terrorists. Russia is also part of the UN-led Geneva Process that has tried without success to bring peace to Syria.  

In the media:  Then there are Moscow’s propaganda efforts, including its repeated insistence that Russia and Assad are fighting only terrorists. Though much of Russia’s military activity in the country did not directly target ISIS as Russia claimed, it did get a propaganda coup in this regard when Russian-backed Syrian troops recaptured Palmyra, the historic city, from ISIS. The Kremlin sent an orchestra to play Bach, Prokofiev, and Shchedri.

When humanitarian groups have complained of airstrikes against hospitals and civilians, Moscow has insisted it was terrorists who were being struck—and it sometimes labels the aid groups terrorists. When there are claims of chemical-weapons attacks—including photographic and video evidence—Russia either blames the rebels for carrying them out, or denies they took place.

Russia has been effective in helping keep Assad in power and away from international consequences. Its intervention in Syria—its first outside Europe since its disaster in Afghanistan—has not proven to be a quagmire, as some had predicted. Indeed, Russian policymakers may believe that their actions in Syria further the nation’s interests in the region. After all, Moscow now has good relations with all of Syria’s neighbors, including Iran and Israel. But its Syria policy has also helped further isolate Russia: It has no major Western allies. And if the United States is indeed planning to strike at the Syrian regime, there won’t be much Russia can do to prevent it, notwithstanding threats to shoot down missiles. Russia will then have to decide whether its internationally condemned ally is worth stepping up to confront a superpower.

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