Long before the exodus from Syria to Europe reached its current peak, an untold number of mostly young male asylum-seekers embarked on the journey as a kind of advance party. One of them was Hussein Ahmad.

Even before that, the route into Europe had already been well used by many, including Iraqis fleeing the carnage of their own civil war. Then, with few welcoming places left in the Mideast, Syrians started to take the route to find European refuge, hoping their families could later follow.

Back then, before the entire world got a glimpse, it was an even longer and riskier journey.

Still, Ahmad was desperate. Home was Raqqa, the seat of power for ISIS. The group had imprisoned him twice for not being observant enough.

The third time they came to his house, he fled out the back door, and the next day was using a way out that would later be successfully used by his wife, Amal, and his two small children — and tens of thousands of other Syrians — to get to Germany.

Last Friday, after a year and a half apart, the family tearfully reunited on Platform 25 of Munich's central train station.

"I'm very, very happy my family reached me, thank God," he said, beaming. "I thank the German government."

A handful of other men stood watching. With no sight of their own loved ones they walked away, clearly disappointed. At least two of them said they too had arrived months ago, using the same route.

Chance of a lifetime

Fathers, sons and husbands who made the journey many months ago are waiting in places like Germany and Sweden for families to follow. It's yet another major pull for many Syrians now making their way to, and across, Europe.

Encouraged by news of the happy reunions and warm welcome in Germany in the past week, many more have left Syria, Iraq, Turkey, Lebanon and beyond, to make the same journey. In my calls to colleagues in Baghdad and Beirut, there are suggestions the flow is about to surge.

For those who have yearned for a better life in Europe, this is the chance of a lifetime.

But the window for a happy conclusion to the story for those now en route may be closing.

The Ahmads are lucky. Their reunion predated word that Germany was starting to strain under the influx it had invited, and they just missed by days the decision to temporarily impose controls at the border with Austria and to send 2,100 riot police to secure it.

Their reunion also comes before tough new Hungarian laws come into effect this week, aimed at stemming the stream of asylum seekers walking across its border, and likely scuttling the plans of thousands trying to get to Germany.

What happens to the refugees currently making their way across Europe when the flow is interrupted, as it inevitably will be, is unclear.

Thousands could soon be stranded

Today, EU member states will be discussing a proposal to more evenly spread the already arrived refugees among them. The idea for a mandatory refugee quota, presented at the European Parliament last week, suggests members resettle 160,000 between them.

Besides the criticism that the number falls far short of what's necessary, working against this proposal will also be the significant differences of opinion among EU members.

Most governments in Europe's East, as well as the U.K., balk at the idea of anyone telling them how many refugees to take in, if any at all. So do many of those countries' citizens, some of whom have erupted in protest to make their anti-refugee views known.

All this means, at some point soon, there will be many more refugees languishing in Europe than apparently anyone is willing or able to cope with.

The first major foreseeable bottleneck will be Hungary's inhospitable border with Serbia. Thousands could become stuck there as winter approaches — kept out by Hungary's new laws, a new fence, and also, if its parliament approves, the deployment of the Hungarian army.

With rail services also more or less shut down now from Budapest to Munich, new routes will surely be sought out, which will affect more countries, and could be more dangerous. Smugglers who were sidelined when Germany and Austria threw open their borders could thrive again.

That carries its own dangers, as we saw with the suffocation of more than 70 refugees in the back of a truck discovered in Austria.

Thousands will likely find themselves stranded in or near countries that do not want them.

Who will then care for the refugees several borders short of their destination and their loved ones?

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