On Tuesday evening, Turkey and Russia announced that they had brokered a cease-fire agreement between the Bashar Assad regime and the opposition that would facilitate the evacuation of civilians and opposition from eastern Aleppo. Buses were dispatched to transport Aleppo residents to Idlib. Hours later, Iran single-handedly sabotaged the last-ditch effort by ordering the Iranian-backed Shiite militias to block the evacuation. Yesterday, attacks against eastern Aleppo resumed.

Having admitted 3 million Syrian refugees and spent close to $15 billion for relief efforts since 2011, Turkey responded to the humanitarian crisis in eastern Aleppo by taking initiative and working with Moscow to find a middle ground. Negotiations held by the Turkish intelligence and the Russian military were intended to prevent the next Srebrenica, while Washington and Brussels opted to watch a bloodthirsty regime massacre innocent people and destroy one of the world heritage cities – as they did in places like former Yugoslavia and Rwanda. Meanwhile, thousands of people gathered outside the diplomatic missions of Russia, Syria and Iran to protest what looked like a 21st century "final solution."

The collapse of the cease-fire agreement should be studied carefully by the Russian leadership. The simple lesson from the past 48 hours is that Assad is not a reliable ally for Moscow. Having bowed to the Kremlin's pressure to abide by the agreement, the Syrian regime played Iran against Russia to continue killing innocent people. To make matters worse, the Russians should also face the fact that they cannot keep a lid on Iran's influence on Syria anymore. At the end of the day, Assad and Tehran made Russian President Vladimir Putin look like a weak leader who cannot deliver his promises – under the watchful eyes of the entire world. It is time for the Kremlin to reconsider their support for the murderer in Damascus.

If you happen to dislike Russia's Middle East policy, you should be really worried about U.S. President Barack Obama's legacy – at least the Russians have courage to talk straight. For years, the Obama administration appeased the Iranian regime and created an echo chamber to present a disastrous foreign policy as a successful initiative. Mistaking PR stunts for actual policy, the White House allowed Tehran get away with a rogue nuclear program. At the same time, Mr. Obama outsourced part of the counterterrorism effort in Syria to Iranian-backed Shiite militias – who now want to exterminate the civilian population of Aleppo because they happen to be Sunni Muslims. Moving forward, Washington's only choice is to acknowledge Mr. Obama's mistakes and support efforts to broker a cease-fire in Syria.

In this sense, the Trump administration should take necessary steps to put an end to Iranian expansionism in the region. The incoming foreign policy team needs to keep in mind that stopping Iran is a key priority if they want to promote stability in the Middle East, keep U.S. allies safe and improve America's reputation on the ground.

The collapse of the Aleppo cease-fire agreement shows that engaging the mullahs in Tehran only encouraged them to break more rules and hope that the West will forget and forgive. To save innocent people in Syria and elsewhere, the international community needs to start talking about ways to keep Iran isolated until they agree to abandon their expansionist and sectarian policies.