Very concerning topic and one the could easily get much worse; aka ship all asylum seekers or for the matter "unwanted" to somewhere willing to take them.
Or "many" as in relative values like "more than 30%"? I have difficulties believing that. If so, it's amazing how coincidental the timing is between the start of the ongoing civil war in Syria and the start of the refugee crisis.
It's also amazing how the UN "has identified 13.5 million Syrians requiring humanitarian assistance, of which 6.6 million are internally displaced within Syria, and over 4.8 million are refugees outside of Syria." - https://en.wikipedia.org/wiki/Refugees_of_the_Syrian_Civil_W... . Are the ones you mentioned in addition to those numbers?
Do you think the numbers are wrong? Why, and by how much do you think they are wrong?
Only 5 million/18 million = 28% of the population has left the country.
For example:
> The Convention further stipulates that, subject to specific exceptions, refugees should not be penalized for their illegal entry or stay. This recognizes that the seeking of asylum can require refugees to breach immigration rules.