Humankind is a thing of wonder. We have proven time and time again that when we decide to come together, we can accomplish extraordinary things. We can go to the moon. We can eradicate polio. We can engineer buildings that reach to the heavens. Now, we can and should mount a global effort to confront the worst humanitarian disaster of our time — the crisis in Syria.

In the 20 years that I've been working in humanitarian aid, this is the most catastrophic disaster I've seen. The depth of human suffering is immense. In terms of scale, it's four times the Haiti earthquake. People in Syria are living on the brink of human need, pushed to the edge. The current escalation of the crisis and the horrible tragedies we've seen on the news are reverberations from the colossal upheaval that has occurred there. They are symptoms of more to come.

We live in an interconnected world where we are only as strong as our weakest link. It's no longer possible to ignore the events that occur halfway around the world. As the reverberations of this crisis hit the shores of Europe, people are suddenly faced with the human tragedy firsthand — the desperation of parents willing to do anything to make a life for their children.

The world is waking up to the crisis. People are increasingly opening their arms to refugees streaming into their countries, lobbying politicians and leaders to resettle them in greater numbers. It's an amazing thing to see, crowds of people gathered, waving signs of welcome to weary and scared refugees. This is an inspiring and incredible movement.

But we need to be careful when calling this a European refugee crisis. This is a bigger problem than allowing people in. This is a bigger problem than resettlement. The problem is at the source. Half of all Syrians have lost their homes. Four million Syrians have left their country, but the vast majority, 7.6 million of them, are still inside Syria. One in three Syrians needs food assistance right now. Their kids haven't been to school in years. We are witnessing the destruction of a country.

The humanitarian response to the Syrian crisis has been operating half-empty for years. There has simply not been enough funding. The aid community has called for increased food aid — its pleas went unanswered, and Syrian families went hungry. What we've seen in the past several months is Syrians reaching their tipping point. They're giving up hope — they will no longer stand by as their children starve. We have simply not done enough to help the people who are looking to save their lives, who are trying to grasp the last shreds of hope for peace. This emerging crisis is only the tip of the iceberg.

Here's the silver lining: In an age of globalization, we can communicate with more people, faster and more effectively than ever before. We have the power to mobilize millions of people with the click of a button. Humanitarian organizations of the world and everyday people are more important than ever — our power lies not only in the delivery of lifesaving things but in the ability to mobilize an international community. We have the tools at our disposal to mount this effort. As humanitarians, as humans, this is what we do.

This is a wake-up call. We need to seize this moment to escalate a global humanitarian response inside Syria. There are organizations working side by side with truly heroic Syrians on the ground, regular people who have risen to the challenge to provide critical humanitarian assistance to their neighbors at great personal risk. These efforts, these people, desperately need support. The time to act is now.

In this line of work, I sometimes come across people who criticize our involvement in what they consider to be matters of little impact on our lives, on our soil. But I have yet to meet that person who can see the human face of a tragedy and be resistant to give. We've all seen that face now, and we've been confronted with the humanity of a crisis of enormous magnitude. People have finally seen people. For four years there's been smoke and noise, and the average person, whether living in Germany or the U.S., couldn't see beyond that. Now I think the smoke has parted, and past the noise and past the politics we've seen that person who is suffering. The person that we are fully capable of helping.

We need to give now, give to someone. Give to anyone that is working at the source, through the political smoke and at the heart of the problem.

There is so much more to do; this is only the beginning. But, imagine for a moment that we live in a world where millions of ordinary citizens mobilized to save a country's people from total devastation. If we can do that, we will have added yet another feat to the list of mankind's greatest accomplishments, one of the most astounding things we have ever done for one another. What a world that would be.

Daniel Wordsworth is president & CEO of the American Refugee Committee, which has headquarters in Minneapolis.