When the Ottoman Turks tried to invade Europe 500 years ago they were defeated at the Gates of Vienna. Today Turkey again has designs on Europe, but it's using a different method.
It's being called Turkey's fifth column in Europe – a vast network of radical Islamists, working inside Turkish mosques and under the control of Turkey's ambitious president, Recep Tayyip Erdogan.
The Austrian government shut down seven mosques and expelled 60 Imams recently because they were being funded illegally by the Turkish government, and because photos from inside the mosques surfaced on the internet showing Turkish children being trained to be martyrs.
Austria's move against the mosques infuriated Turkey's government, and President Erdogan warned of a "coming war between the cross and the crescent."
The leading expert on Erdogan's network of mosques and Islamic associations in Europe, Turkish journalist Abdullah Bozkurt of the Stockholm Center for Freedom, calls them Erdogan's fifth column. He spoke to CBN News from Stockholm, Sweden.
"What we have been seeing in the last couple of years – an increase of activity on the part of the Turkish government to turn the mosques that were financed by the Turkish community and by the Turkish government, or imams that were deployed directly from Turkey, as sort of political operatives," he said.
There are an estimated five million Turks in Germany and millions more across Europe. Bozkurt says several Islamic and charitable organizations run by the Turkish government are fronts for political activity.
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Shocking images show Erdogan supporters and Kurds fighting on the streets in Belgium. Bozkurt says Erdogan's network is a proxy force that can cause social unrest on the streets of Europe and keep Muslims there in line.
"This is first and foremost a threat to the Muslims actually living in Europe and other countries because anybody who is not subscribing to this ideology of their own government is deemed a threat, traitors, not patriotic and terrorists or not even Muslim…infidels," he told CBN.
Bozkurt says Erdogan's fifth column is a strong card he can play if he needs to strike back at Europe.