The mass graves and bombed-out cities targeted by Russian forces in Ukraine have shocked the civilized world. But to Syrian war refugees and Syrian-born Americans like myself, Vladimir Putin’s barbaric assault on Ukraine is less a shock than it is a grim reminder of the overwhelming destructive forces he and his fellow dictator, Syria’s Bashar Al-Assad, unleashed on our home country over a decade ago.

The West’s response to Putin’s invasion of Ukraine has been swift. Yet the ongoing Syrian crisis, which began in 2011 when protesters rose up against Assad’s repressive government, is now, tragically, all but ignored.

It’s a mistake to see these two conflicts as separate. The failure of the United States and its allies to stand up to the Russian-backed Assad government opened the door for Putin to wage allout war against Ukraine. Unless Western leaders commit to helping Syria’s opposition topple Assad and achieve the Syrian people’s aspiration to transition to a democratic country, the world will remain needlessly vulnerable to the whims of dictators.

In the first years of Syria’s civil war, opposition forces made steady progress, gaining control of large segments of several provinces. That all changed in 2015, when Putin came to the aid of Assad. Putin’s forces didn’t just bomb military targets — they intentionally bombed schools, hospitals, and markets, killing 24,743 defenseless civilians, by one estimate, and leading to the world’s largest refugee crisis since World War II.

My own brother, along with his wife and children, were forced to flee the Damascus suburb of Ghouta to avoid the bombings and a terrifying chemical attack that killed scores of their neighbors. They joined tens of thousands of Syrians who fled to overcrowded and unsanitary refugee camps in Idlib.

These joint Russian-Syrian assaults were critical in helping Assad stave off opposition forces. But for Putin, they were a proving ground for tactics he would later deploy in Ukraine.

And it’s here that the connection between these wars is most critical. Had the United States and other Western countries rallied behind Syria’s opposition, it would have sent a strong message to Assad and Putin both. Specifically, it would have shown these dictators that targeted assaults on helpless civilians won’t be tolerated, no matter where they occur.

But no such response materialized. At no point has the United States ever provided enough support to the Syrian opposition to even remotely threaten Assad’s power, much less Putin’s. Putin was permitted to perpetrate horrific war crimes against the civilians of another nation with impunity. Is it any wonder he believed he could do the same in Ukraine?

Thankfully, the West has taken notice, showing solidarity with those fighting for their freedom in Ukraine. But an effective response to Putin’s uncivilized behavior can’t ignore his past and ongoing crimes against the Syrian people.

It’s time for the West to make up for its failure in Syria, and finally provide my home nation’s opposition forces with the support they need to beat back both Assad and Putin and achieve the Syrian people’s desire to transition to democracy.

Dr. Tarek Kteleh is a practicing medical doctor, president of Rheumatology of

Central Indiana, and a member of Citizens for a Secure and Safe America, a nongovernmental organization whose mission is to promote security in the Middle East and democratic progress in Syria.