On Sunday, Germany introduced temporary controls on its border with Austria to cope with the influx of refugees. There have been rising complaints about the excessive numbers of refugees, pressuring the government to tighten its refugee policy sooner or later. Within the EU, member states are more divided about the refugee crisis, while waves of refugees keep coming into this continent.

German society has taken a respectable humanitarian approach toward the refugees. But the attitude of the Angela Merkel government has encouraged more refugees to make Germany their final destination.

As the majority of European countries are unwilling to accept the compulsory quota scheme, the crisis will deal a heavy blow to the unity of the EU and escalate into a systematic crisis.

If the influx of refugees cannot be put under control, then it means the Syrian war will spread across Europe, which will have to bear the pain of Syria.

Things may get worse. Some Iraqis and Afghans have joined the refugees bound for Europe. They may overwhelm any of Europe's humanitarian schemes, possibly resulting in conflicts between Western society and the refugee groups.

European countries are battling over the exact number of refugees they should take in. They may have underestimated the severity of the issue. The EU's legitimacy to refuse the refugees has already been challenged. Refugees from Syria and a wider region have posed a humanitarian pressure on Europe. More people will strive to set foot on this land. This is an extended outcome of the Syrian war.

Europe and the US haven't made clear or are unwilling to admit the root cause of the problem. They have no intention or means to end the civil war in Syria.

Should they partner with the Assad regime to wipe out the Islamic State and then accept the regime to promote the reconciliation of the country, or should they still make Assad an enemy and allow the country to be dragged into long-term chaos, which may result in more refugees into this continent? Europe must face this core choice.

The flow of refugees predicts a new scenario brought about by war in this globalized era. The unprecedented trans-border flow of refugees will escalate the disaster. It is more likely that the international community has to bear the cost of a war that happened in a single country.

Germany has done all it can, but it cannot control how the current crisis will evolve.

All kinds of sentiments associated with the influx of refugees just started to emerge, and the devastating effects will be difficult to avoid.